diff --git a/radio/src/FatFs/ff.c b/radio/src/FatFs/ff.c
index aa640f89f..3c87bc3b1 100644
--- a/radio/src/FatFs/ff.c
+++ b/radio/src/FatFs/ff.c
@@ -3073,6 +3073,11 @@ FRESULT f_opendir (
 }
 
 
+FRESULT f_closedir (DIR * rep)
+{
+	//apparently nothing to do in FatFS
+	return FR_OK;
+}
 
 
 /*-----------------------------------------------------------------------*/
diff --git a/radio/src/FatFs/ff.h b/radio/src/FatFs/ff.h
index b4115f610..9d4b865f8 100644
--- a/radio/src/FatFs/ff.h
+++ b/radio/src/FatFs/ff.h
@@ -209,6 +209,7 @@ FRESULT f_read (FIL* fp, void* buff, UINT btr, UINT* br);			/* Read data from a
 FRESULT f_lseek (FIL* fp, DWORD ofs);								/* Move file pointer of a file object */
 FRESULT f_close (FIL* fp);											/* Close an open file object */
 FRESULT f_opendir (DIR* dj, const TCHAR* path);						/* Open an existing directory */
+FRESULT f_closedir (DIR * rep);
 FRESULT f_readdir (DIR* dj, FILINFO* fno);							/* Read a directory item */
 FRESULT f_stat (const TCHAR* path, FILINFO* fno);					/* Get file status */
 FRESULT f_write (FIL* fp, const void* buff, UINT btw, UINT* bw);	/* Write data to a file */
diff --git a/radio/src/Makefile b/radio/src/Makefile
index c53697ccf..281c1851b 100644
--- a/radio/src/Makefile
+++ b/radio/src/Makefile
@@ -297,6 +297,13 @@ CHANNELS_MONITOR_INV_HIDE = NO
 # Values = NO, YES
 NANO = NO
 
+# Use custom bin based allocator for Lua
+# Values = NO, YES
+# YES - use our bin based allocator
+# NO - use default Lua allocator
+USE_BIN_ALLOCATOR = NO
+
+
 # Enable trace of events into Trace Buffer for debugging purposes
 # Activating any of these options also activates DEBUG and DEBUG_TRACE_BUFFER
 # Values = NO, YES
@@ -776,6 +783,10 @@ ifeq ($(PCB), TARANIS)
            lua/src/lbaselib.c lua/src/linit.c lua/src/lmathlib.c lua/src/lbitlib.c lua/src/loadlib.c lua/src/lauxlib.c lua/src/ltablib.c lua/src/lcorolib.c
     SRC += $(LUASRC) 
     LUADEP = lua_exports.cpp
+	ifeq ($(USE_BIN_ALLOCATOR), YES)
+	  CPPDEFS += -DUSE_BIN_ALLOCATOR
+	  CPPSRC += bin_allocator.cpp
+	endif
   endif           
   ifeq ($(SDCARD), YES)
     EXTRABOARDSRC += FatFs/ff.c FatFs/fattime.c FatFs/option/ccsbcs.c targets/taranis/diskio.cpp
diff --git a/radio/src/audio_arm.cpp b/radio/src/audio_arm.cpp
index 1d096e558..306f11da8 100644
--- a/radio/src/audio_arm.cpp
+++ b/radio/src/audio_arm.cpp
@@ -274,6 +274,7 @@ void referenceSystemAudioFiles()
         }
       }
     }
+    f_closedir(&dir);
   }
 
   sdAvailableSystemAudioFiles = availableAudioFiles;
@@ -395,6 +396,7 @@ void referenceModelAudioFiles()
         }
       }
     }
+    f_closedir(&dir);
   }
 }
 
diff --git a/radio/src/bin_allocator.cpp b/radio/src/bin_allocator.cpp
new file mode 100644
index 000000000..f74e351f2
--- /dev/null
+++ b/radio/src/bin_allocator.cpp
@@ -0,0 +1,111 @@
+#include <stdlib.h>
+#include <string.h>
+#include "opentx.h"
+#include "bin_allocator.h"
+
+
+BinAllocator_slots1 slots1;
+BinAllocator_slots2 slots2;
+
+#if defined(DEBUG)
+int SimulateMallocFailure = 0;    //set this to simulate allocation failure
+#endif 
+
+bool bin_free(void * ptr)
+{
+  //return TRUE if ours
+  return slots1.free(ptr) || slots2.free(ptr);
+}
+
+void * bin_malloc(size_t size) {
+  //try to allocate from our space
+  void * res = slots1.malloc(size);
+  return res ? res : slots2.malloc(size);
+}
+
+void * bin_realloc(void * ptr, size_t size)
+{
+  if (ptr == 0) {
+    //no previous data, try our malloc
+    return bin_malloc(size);
+  }
+  else {
+    if (! (slots1.is_member(ptr) || slots2.is_member(ptr)) ) {
+      // not our data, leave it to libc realloc
+      return 0;
+    }
+
+    //we have existing data
+    // if it fits in current slot, return it
+    // TODO if new size is smaller, try to relocate in smaller slot
+    if ( slots1.can_fit(ptr, size) ) {
+      // TRACE("OUR realloc %p[%lu] fits in slot1", ptr, size); FLUSH();
+      return ptr;
+    }
+    if ( slots2.can_fit(ptr, size) ) {
+      // TRACE("OUR realloc %p[%lu] fits in slot2", ptr, size); FLUSH();
+      return ptr;
+    }
+
+    //we need a bigger slot
+    void * res = bin_malloc(size);
+    if (res == 0) {
+      // we don't have the space, use libc malloc
+      // TRACE("bin_malloc [%lu] FAILURE", size); FLUSH();
+      res = malloc(size);
+      if (res == 0) {
+        TRACE("libc malloc [%lu] FAILURE", size); FLUSH();  
+        return 0;
+      }
+    }
+    //copy data
+    memcpy(res, ptr, slots1.size(ptr) + slots2.size(ptr));
+    bin_free(ptr);
+    return res;
+  }
+}
+
+
+void *bin_l_alloc (void *ud, void *ptr, size_t osize, size_t nsize)
+{
+  (void)ud; (void)osize;  /* not used */
+  if (nsize == 0) {
+    if (ptr) {   // avoid a bunch of NULL pointer free calls
+      if (!bin_free(ptr)) {
+        // not our range, use libc allocator
+        // TRACE("libc free %p", ptr); FLUSH();
+        free(ptr);
+      }
+    }
+    return NULL;
+  }
+  else {
+#if defined(DEBUG)
+    if (SimulateMallocFailure < 0 ) {
+      //delayed failure
+      if (++SimulateMallocFailure == 0) {
+        SimulateMallocFailure = 1;
+      }
+    }
+    if ( SimulateMallocFailure > 0) {
+      // simulate one malloc failure
+      TRACE("bin_l_alloc(): simulating malloc failure at %p[%lu]", ptr, nsize); FLUSH();
+      return 0;
+    }
+#endif // #if defined(DEBUG)
+    // try our allocator, if it fails use libc allocator
+    void * res = bin_realloc(ptr, nsize);
+    if (res && ptr) {
+      // TRACE("OUR realloc %p[%lu] -> %p[%lu]", ptr, osize, res, nsize); FLUSH(); 
+    }
+    if (res == 0) {
+      res = realloc(ptr, nsize);
+      // TRACE("libc realloc %p[%lu] -> %p[%lu]", ptr, osize, res, nsize); FLUSH();
+      // if (res == 0 ){
+      //   TRACE("realloc FAILURE %lu", nsize);
+      //   dumpFreeMemory();
+      // }
+    }
+    return res;
+  }
+}
diff --git a/radio/src/bin_allocator.h b/radio/src/bin_allocator.h
new file mode 100644
index 000000000..1c50fb75b
--- /dev/null
+++ b/radio/src/bin_allocator.h
@@ -0,0 +1,78 @@
+#ifndef binallocator_h
+#define binallocator_h
+
+#include "debug.h"
+
+template <int SIZE_SLOT, int NUM_BINS> class BinAllocator {
+private:
+  PACK(struct Bin {
+    char data[SIZE_SLOT];
+    bool Used;
+  });
+  struct Bin Bins[NUM_BINS];
+  int NoUsedBins;
+public:
+  BinAllocator() : NoUsedBins(0) {
+    memclear(Bins, sizeof(Bins));
+  }
+  bool free(void * ptr) {
+    for (size_t n = 0; n < NUM_BINS; ++n) {
+      if (ptr == Bins[n].data) {
+        Bins[n].Used = false;
+        --NoUsedBins;
+        // TRACE("\tBinAllocator<%d> free %lu ------", SIZE_SLOT, n); FLUSH();
+        return true;
+      }
+    }
+    return false;
+  }
+  bool is_member(void * ptr) {
+    return (ptr >= Bins[0].data && ptr <= Bins[NUM_BINS-1].data);
+  }
+  void * malloc(size_t size) {
+    if (size > SIZE_SLOT) {
+      // TRACE("BinAllocator<%d> malloc [%lu] size > SIZE_SLOT", SIZE_SLOT, size); FLUSH();
+      return 0;
+    }
+    if (NoUsedBins >= NUM_BINS) {
+      // TRACE("BinAllocator<%d> malloc [%lu] no free slots", SIZE_SLOT, size); FLUSH();
+      return 0;
+    }
+    for (size_t n = 0; n < NUM_BINS; ++n) {
+      if (!Bins[n].Used) {
+        Bins[n].Used = true;
+        ++NoUsedBins;
+        // TRACE("\tBinAllocator<%d> malloc %lu[%lu]", SIZE_SLOT, n, size); FLUSH();
+        return Bins[n].data;
+      }
+    }
+    // TRACE("BinAllocator<%d> malloc [%lu] no free slots", SIZE_SLOT , size); FLUSH();
+    return 0;
+  }
+  size_t size(void * ptr) {
+    return is_member(ptr) ? SIZE_SLOT : 0;
+  }
+  bool can_fit(void * ptr, size_t size) {
+    return is_member(ptr) && size <= SIZE_SLOT;  //todo is_member check is redundant
+  }
+  unsigned int capacity() { return NUM_BINS; }
+  unsigned int size() { return NoUsedBins; }
+};
+
+#if defined(SIMU)
+typedef BinAllocator<39,300> BinAllocator_slots1;
+typedef BinAllocator<79,100> BinAllocator_slots2;
+#else
+typedef BinAllocator<29,200> BinAllocator_slots1;
+typedef BinAllocator<91,50> BinAllocator_slots2;
+#endif
+
+#if defined(USE_BIN_ALLOCATOR)
+extern BinAllocator_slots1 slots1;
+extern BinAllocator_slots2 slots2;
+
+// wrapper for our BinAllocator for Lua
+void *bin_l_alloc (void *ud, void *ptr, size_t osize, size_t nsize);
+#endif   //#if defined(USE_BIN_ALLOCATOR)
+
+#endif //binallocator_h
diff --git a/radio/src/debug.cpp b/radio/src/debug.cpp
index a50338443..4ed6d4c3d 100644
--- a/radio/src/debug.cpp
+++ b/radio/src/debug.cpp
@@ -137,6 +137,13 @@ static void dispw_256( register uint32_t address, register uint32_t lines )
 	}
 }
 
+extern Fifo<512> uart3TxFifo;
+
+void debugFlush() 
+{
+  uart3TxFifo.flush();
+}
+
 void debugTask(void* pdata)
 {
   uint8_t rxchar ;
diff --git a/radio/src/debug.h b/radio/src/debug.h
index 4fe093f62..dc5880eec 100644
--- a/radio/src/debug.h
+++ b/radio/src/debug.h
@@ -52,6 +52,8 @@
 #define TRACE_WARNING(...)    do { printf("-W- " __VA_ARGS__); fflush(stdout); } while(0)
 #define TRACE_WARNING_WP(...) do { printf(__VA_ARGS__); fflush(stdout); } while(0)
 #define TRACE_ERROR(...)      do { printf("-E- " __VA_ARGS__); fflush(stdout); } while(0)
+#define FLUSH()
+
 inline void dump(void * data, unsigned int size)
 {
   unsigned char *uchar_data = (unsigned char *)data;
@@ -78,6 +80,7 @@ extern "C" {
 
 void debugPuts(const char *string, ...);
 void dump(unsigned char *data, unsigned int size);
+void debugFlush();
 
 #ifdef __cplusplus
 }
@@ -92,7 +95,7 @@ void dump(unsigned char *data, unsigned int size);
 #define TRACE_WARNING(...)    debugPuts("-W- " __VA_ARGS__)
 #define TRACE_WARNING_WP(...) debugPuts(__VA_ARGS__)
 #define TRACE_ERROR(...)      debugPuts("-E- " __VA_ARGS__)
-
+#define FLUSH()               debugFlush();
 void debugTask(void* pdata);
 
 #else
@@ -106,6 +109,7 @@ void debugTask(void* pdata);
 #define TRACE_WARNING(...) { }
 #define TRACE_WARNING_WP(...) { }
 #define TRACE_ERROR(...) { }
+#define FLUSH()
 
 #endif
 
diff --git a/radio/src/eeprom_raw.cpp b/radio/src/eeprom_raw.cpp
index b3d2704e3..dafde85ef 100644
--- a/radio/src/eeprom_raw.cpp
+++ b/radio/src/eeprom_raw.cpp
@@ -682,6 +682,9 @@ const pm_char * eeBackupModel(uint8_t i_fileSrc)
     if (result != FR_OK)
       return SDCARD_ERROR(result);
   }
+  else {
+    f_closedir(&archiveFolder);
+  }
 
   buf[sizeof(MODELS_PATH)-1] = '/';
   strcpy(strcat_modelname(&buf[sizeof(MODELS_PATH)], i_fileSrc), STR_MODELS_EXT);
diff --git a/radio/src/fifo.h b/radio/src/fifo.h
index b5d41338f..bb18dab09 100644
--- a/radio/src/fifo.h
+++ b/radio/src/fifo.h
@@ -47,10 +47,6 @@ class Fifo
     {
     }
 
-    bool empty() {
-      return (ridx == widx);
-    }
-
     void push(uint8_t byte) {
       uint32_t next = (widx+1) & (N-1);
       if (next != ridx) {
@@ -69,6 +65,12 @@ class Fifo
         return true;
       }
     }
+    bool empty() {
+      return (ridx == widx);
+    }
+    void flush() {
+      while (!empty()) {};
+    }
 
   protected:
     uint8_t fifo[N];
diff --git a/radio/src/lua.cpp b/radio/src/lua.cpp
index dece1af6d..c7fa4a516 100644
--- a/radio/src/lua.cpp
+++ b/radio/src/lua.cpp
@@ -38,6 +38,7 @@
 #include <stdio.h>
 #include "opentx.h"
 #include "stamp-opentx.h"
+#include "bin_allocator.h"
 
 #if !defined(SIMU)
 extern "C" {
@@ -1566,7 +1567,11 @@ void luaInit()
 {
   luaClose();
   if (luaState != INTERPRETER_PANIC) {
-    L = luaL_newstate();
+#if defined(USE_BIN_ALLOCATOR)
+    L = lua_newstate(bin_l_alloc, NULL);   //we use our own allocator!
+#else
+    L = lua_newstate(l_alloc, NULL);   //we use Lua default allocator
+#endif
     if (L) {
       // install our panic handler
       lua_atpanic(L, &custom_lua_atpanic);
diff --git a/radio/src/lua/src/lauxlib.c b/radio/src/lua/src/lauxlib.c
index 1c52b82a6..b548fe297 100644
--- a/radio/src/lua/src/lauxlib.c
+++ b/radio/src/lua/src/lauxlib.c
@@ -954,10 +954,13 @@ LUALIB_API const char *luaL_gsub (lua_State *L, const char *s, const char *p,
 }
 
 
-static void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
+void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize) {
   (void)ud; (void)osize;  /* not used */
   if (nsize == 0) {
-    free(ptr);
+    if (ptr) {   // avoid a bunch of NULL pointer free calls
+      // TRACE("free %p", ptr); FLUSH();
+      free(ptr);
+    }
     return NULL;
   }
   else
diff --git a/radio/src/lua/src/lauxlib.h b/radio/src/lua/src/lauxlib.h
index bb2ba5e97..6cc922e12 100644
--- a/radio/src/lua/src/lauxlib.h
+++ b/radio/src/lua/src/lauxlib.h
@@ -93,6 +93,8 @@ LUALIB_API int (luaL_len) (lua_State *L, int idx);
 LUALIB_API const char *(luaL_gsub) (lua_State *L, const char *s, const char *p,
                                                   const char *r);
 
+LUALIB_API void *l_alloc (void *ud, void *ptr, size_t osize, size_t nsize);
+
 LUALIB_API void (luaL_setfuncs) (lua_State *L, const luaL_Reg *l, int nup);
 
 LUALIB_API int (luaL_getsubtable) (lua_State *L, int idx, const char *fname);
diff --git a/radio/src/lua/src/ldo.c b/radio/src/lua/src/ldo.c
index 32d6e5ed4..c301030d6 100644
--- a/radio/src/lua/src/ldo.c
+++ b/radio/src/lua/src/ldo.c
@@ -205,6 +205,12 @@ static int stackinuse (lua_State *L) {
 void luaD_shrinkstack (lua_State *L) {
   int inuse = stackinuse(L);
   int goodsize = inuse + (inuse / 8) + 2*EXTRA_STACK;
+  if ((L->stacksize - goodsize) < 40) {
+    //skip shrink
+    // TRACE("luaD_shrinkstack(skip): L->stacksize: %d, goodsize: %d", L->stacksize, goodsize);
+    return;
+  }
+  // TRACE("luaD_shrinkstack(): L->stacksize: %d, goodsize: %d", L->stacksize, goodsize);
   if (goodsize > LUAI_MAXSTACK) goodsize = LUAI_MAXSTACK;
   if (inuse > LUAI_MAXSTACK ||  /* handling stack overflow? */
       goodsize >= L->stacksize)  /* would grow instead of shrink? */
diff --git a/radio/src/lua/src/lua.h b/radio/src/lua/src/lua.h
index 5dc0db202..cf4af4634 100644
--- a/radio/src/lua/src/lua.h
+++ b/radio/src/lua/src/lua.h
@@ -11,10 +11,10 @@
 
 #include <stdarg.h>
 #include <stddef.h>
-
+#include <inttypes.h>
 
 #include "luaconf.h"
-
+#include "debug.h"
 
 #define LUA_VERSION_MAJOR	"5"
 #define LUA_VERSION_MINOR	"2"
diff --git a/radio/src/lua/src/luaconf.h b/radio/src/lua/src/luaconf.h
index 4d96f2c77..b55800073 100644
--- a/radio/src/lua/src/luaconf.h
+++ b/radio/src/lua/src/luaconf.h
@@ -11,9 +11,9 @@
 #include <limits.h>
 #include <stddef.h>
 
-#include "debug.h"
-
+#if defined(SDCARD)
 #define USE_FATFS
+#endif
 
 /*
 ** ==================================================================
diff --git a/radio/src/simu.cpp b/radio/src/simu.cpp
index 61b0f011a..02dc22eec 100644
--- a/radio/src/simu.cpp
+++ b/radio/src/simu.cpp
@@ -55,6 +55,7 @@ class Open9xSim: public FXMainWindow
   public:
     Open9xSim(){};
     Open9xSim(FXApp* a);
+    ~Open9xSim();
     long onKeypress(FXObject*,FXSelector,void*);
     long onTimeout(FXObject*,FXSelector,void*);
     void makeSnapshot(const FXDrawable* drawable);
@@ -67,7 +68,7 @@ class Open9xSim: public FXMainWindow
     bool           firstTime;
 
   public:
-    FXSlider      *sliders[8];
+    FXSlider      *sliders[NUM_STICKS];
     FXKnob        *knobs[NUM_POTS];
 };
 
@@ -127,6 +128,24 @@ Open9xSim::Open9xSim(FXApp* a):
   getApp()->addTimeout(this,2,100);
 }
 
+Open9xSim::~Open9xSim()
+{
+  StopMainThread();
+  StopEepromThread();
+  
+  delete bmp;
+  delete sliders[0];
+  delete sliders[1];
+  delete sliders[2];
+  delete sliders[3];
+
+  for(int i=0; i<NUM_POTS; i++){
+    delete knobs[i];
+  }
+
+  delete bmf;
+}
+
 void Open9xSim::makeSnapshot(const FXDrawable* drawable)
 {
      // Construct and create an FXImage object
diff --git a/radio/src/targets/simu/simpgmspace.cpp b/radio/src/targets/simu/simpgmspace.cpp
index ac2f29c12..a8758c0fc 100644
--- a/radio/src/targets/simu/simpgmspace.cpp
+++ b/radio/src/targets/simu/simpgmspace.cpp
@@ -323,6 +323,11 @@ void *main_thread(void *)
       perMain();
       sleep(10/*ms*/);
     }
+
+#if defined(LUA)
+    luaClose();
+#endif
+
 #ifdef SIMU_EXCEPTIONS
   }
   catch (...) {
@@ -396,6 +401,14 @@ void StopEepromThread()
   sem_post(eeprom_write_sem);
   pthread_join(eeprom_thread_pid, NULL);
 #endif
+#ifdef __APPLE__
+  //TODO free semaphore eeprom_write_sem
+#else
+  sem_destroy(eeprom_write_sem);
+  free(eeprom_write_sem);
+#endif
+
+  if (fp) fclose(fp);
 }
 
 #if defined(PCBTARANIS)
@@ -546,6 +559,13 @@ FRESULT f_opendir (DIR * rep, const TCHAR * name)
   return FR_OK;
 }
 
+FRESULT f_closedir (DIR * rep)
+{
+  TRACE("f_closedir(%p)", rep);
+  simu::closedir((simu::DIR *)rep->fs);
+  return FR_OK;
+}
+
 FRESULT f_readdir (DIR * rep, FILINFO * fil)
 {
   if (!rep->fs) return FR_NO_FILE;
diff --git a/radio/src/targets/simu/simpgmspace.h b/radio/src/targets/simu/simpgmspace.h
index 212983271..4325e92fd 100644
--- a/radio/src/targets/simu/simpgmspace.h
+++ b/radio/src/targets/simu/simpgmspace.h
@@ -356,7 +356,9 @@ void simuSetTrim(uint8_t trim, bool state);
 void simuSetSwitch(uint8_t swtch, int8_t state);
 
 void StartMainThread(bool tests=true);
+void StopMainThread();
 void StartEepromThread(const char *filename="eeprom.bin");
+void StopEepromThread();
 
 extern const char *eepromFile;
 #if defined(PCBTARANIS) || defined(PCBACT)