diff --git a/NEWS b/NEWS
index 70fe9e26f..29fdbb15a 100644
--- a/NEWS
+++ b/NEWS
@@ -13,6 +13,7 @@ Version 5.x -- future
         * Change FT1000MP Mark V model names to align with FT1000MP
 
 Version 4.6
+        * Added RIG_FUNC_SYNC for FTDX101D/MP
         * Added Barrett 4100
         * Added DL2MAN (tr)uSDX -- needs refinement
         * Added Thetis entry -- derived from FlexRadio/Apache PowerSDR
diff --git a/include/hamlib/rig.h b/include/hamlib/rig.h
index 8bcb4df7c..c34003d80 100644
--- a/include/hamlib/rig.h
+++ b/include/hamlib/rig.h
@@ -1272,7 +1272,7 @@ typedef uint64_t setting_t;
 #define RIG_FUNC_SEND_MORSE CONSTANT_64BIT_FLAG (45)   /*!< \c SEND_MORSE -- Send specified characters using CW */
 #define RIG_FUNC_SEND_VOICE_MEM CONSTANT_64BIT_FLAG (46)   /*!< \c SEND_VOICE_MEM -- Transmit in SSB message stored in memory */
 #define RIG_FUNC_OVF_STATUS CONSTANT_64BIT_FLAG (47)   /*!< \c OVF -- Read overflow status 0=Off, 1=On */
-#define RIG_FUNC_BIT48      CONSTANT_64BIT_FLAG (48)   /*!< \c available for future RIG_FUNC items */
+#define RIG_FUNC_SYNC       CONSTANT_64BIT_FLAG (48)   /*!< \c Synchronize VFOS -- FTDX101D/MP for now SY command  */
 #define RIG_FUNC_BIT49      CONSTANT_64BIT_FLAG (49)   /*!< \c available for future RIG_FUNC items */
 #define RIG_FUNC_BIT50      CONSTANT_64BIT_FLAG (50)   /*!< \c available for future RIG_FUNC items */
 #define RIG_FUNC_BIT51      CONSTANT_64BIT_FLAG (51)   /*!< \c available for future RIG_FUNC items */
@@ -3845,6 +3845,7 @@ extern HAMLIB_EXPORT(char*) rig_date_strget(char *buf, int buflen, int localtime
 enum GPIO { GPIO1, GPIO2, GPIO3, GPIO4 };
 extern HAMLIB_EXPORT(int) rig_cm108_get_bit(hamlib_port_t *p, enum GPIO gpio, int *bit);
 extern HAMLIB_EXPORT(int) rig_cm108_set_bit(hamlib_port_t *p, enum GPIO gpio, int bit);
+extern HAMLIB_EXPORT(int) rig_band_changed(RIG *rig, hamlib_bandselect_t band);
 
 extern HAMLIB_EXPORT(void *) rig_data_pointer(RIG *rig, rig_ptrx_t idx);
 
diff --git a/rigs/yaesu/ftdx101.h b/rigs/yaesu/ftdx101.h
index fd830f1c5..64a433a3c 100644
--- a/rigs/yaesu/ftdx101.h
+++ b/rigs/yaesu/ftdx101.h
@@ -65,7 +65,8 @@
 #define FTDX101_FUNCS (RIG_FUNC_TONE|RIG_FUNC_TSQL|RIG_FUNC_LOCK|\
                RIG_FUNC_MON|RIG_FUNC_NB|RIG_FUNC_NR|RIG_FUNC_VOX|\
                RIG_FUNC_FBKIN|RIG_FUNC_COMP|RIG_FUNC_ANF|RIG_FUNC_MN|\
-               RIG_FUNC_RIT|RIG_FUNC_XIT|RIG_FUNC_TUNER|RIG_FUNC_APF)
+               RIG_FUNC_RIT|RIG_FUNC_XIT|RIG_FUNC_TUNER|RIG_FUNC_APF|\
+               RIG_FUNC_SYNC)
 
 /* TBC */
 #define FTDX101_VFO_OPS (RIG_OP_TUNE|RIG_OP_CPY|RIG_OP_XCHG|\
diff --git a/rigs/yaesu/newcat.c b/rigs/yaesu/newcat.c
index f9360c8d1..946bc1e89 100644
--- a/rigs/yaesu/newcat.c
+++ b/rigs/yaesu/newcat.c
@@ -6435,6 +6435,16 @@ int newcat_set_func(RIG *rig, vfo_t vfo, setting_t func, int status)
 
         break;
 
+    case RIG_FUNC_SYNC:
+        if (!newcat_valid_command(rig, "SY"))
+        {
+            RETURNFUNC(-RIG_ENAVAIL);
+        }
+
+        SNPRINTF(priv->cmd_str, sizeof(priv->cmd_str), "SY%d%c", status ? 1 : 0,
+                 cat_term);
+        break;
+
     default:
         RETURNFUNC(-RIG_EINVAL);
     }
@@ -6728,6 +6738,15 @@ int newcat_get_func(RIG *rig, vfo_t vfo, setting_t func, int *status)
 
         break;
 
+    case RIG_FUNC_SYNC:
+        if (!newcat_valid_command(rig, "SY"))
+        {
+            RETURNFUNC(-RIG_ENAVAIL);
+        }
+
+        SNPRINTF(priv->cmd_str, sizeof(priv->cmd_str), "SY%c", cat_term);
+        break;
+
     default:
         RETURNFUNC(-RIG_EINVAL);
     }
@@ -6842,6 +6861,10 @@ int newcat_get_func(RIG *rig, vfo_t vfo, setting_t func, int *status)
 
         break;
 
+    case RIG_FUNC_SYNC:
+        *status = (retfunc[0] == '1') ? 1 : 0;
+        break;
+
     default:
         RETURNFUNC(-RIG_EINVAL);
     }
diff --git a/rigs/yaesu/newcat.h b/rigs/yaesu/newcat.h
index d3a722eae..6951fa310 100644
--- a/rigs/yaesu/newcat.h
+++ b/rigs/yaesu/newcat.h
@@ -50,7 +50,7 @@
 typedef char ncboolean;
 
 /* shared function version */
-#define NEWCAT_VER "20240113"
+#define NEWCAT_VER "20240118"
 
 /* Hopefully large enough for future use, 128 chars plus '\0' */
 #define NEWCAT_DATA_LEN                 129
diff --git a/src/band_changed.c b/src/band_changed.c
index 075f46ce2..848bef0bb 100644
--- a/src/band_changed.c
+++ b/src/band_changed.c
@@ -2,7 +2,7 @@
 // Can customize during build
 // Eventually should improved this for external actions when
 // rigctld gets integrated as a service within Hamlib
-int rig_band_changed(RIG *rig, hamlib_bandselect_t band)
+int HAMLIB_API rig_band_changed(RIG *rig, hamlib_bandselect_t band)
 {
     // See band_changed.c
     // Examples:
diff --git a/src/misc.c b/src/misc.c
index c9000156c..6f13236aa 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -740,6 +740,7 @@ static const struct
     { RIG_FUNC_SEND_MORSE, "SEND_MORSE" },
     { RIG_FUNC_SEND_VOICE_MEM, "SEND_VOICE_MEM" },
     { RIG_FUNC_OVF_STATUS, "OVF_STATUS" },
+    { RIG_FUNC_SYNC, "SYNC" },
     { RIG_FUNC_NONE, "" },
 };
 
diff --git a/src/rig.c b/src/rig.c
index 751180729..08a9da292 100644
--- a/src/rig.c
+++ b/src/rig.c
@@ -588,7 +588,7 @@ RIG *HAMLIB_API rig_init(rig_model_t rig_model)
     rp = RIGPORT(rig);
     pttp = PTTPORT(rig);
     dcdp = DCDPORT(rig);
-    
+
     rs->rig_model = caps->rig_model;
     rs->priv = NULL;
     rs->async_data_enabled = 0;
@@ -1311,7 +1311,7 @@ int HAMLIB_API rig_open(RIG *rig)
     case RIG_DCD_GPIO:
     case RIG_DCD_GPION:
         dcdp->fd = gpio_open(dcdp, 0,
-                                   RIG_DCD_GPION == dcdp->type.dcd ? 0 : 1);
+                             RIG_DCD_GPION == dcdp->type.dcd ? 0 : 1);
 
         if (dcdp->fd < 0)
         {
@@ -1961,6 +1961,7 @@ int rig_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
     vfo_t vfo_save;
     static int last_band = -1;
     int curr_band;
+    int band_changing = 0;
 
     if (CHECK_RIG_ARG(rig))
     {
@@ -1974,7 +1975,8 @@ int rig_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
     {
         rig_debug(RIG_DEBUG_VERBOSE, "%s: band changing to %s\n", __func__,
                   rig_get_band_str(rig, curr_band, 0));
-        rig_band_changed(rig, curr_band);
+        band_changing = 1;
+        //rig_band_changed(rig, curr_band);
         last_band = curr_band;
     }
 
@@ -2106,8 +2108,13 @@ int rig_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
 
         do
         {
-            HAMLIB_TRACE;
             retcode = caps->set_freq(rig, vfo, freq);
+
+            if (band_changing)
+            {
+                rig_band_changed(rig, curr_band);
+            }
+
             // disabling the freq check as of 2023-06-02
             // seems unnecessary and slows down rigs unnecessarily
             tfreq = freq;
@@ -2196,6 +2203,9 @@ int rig_set_freq(RIG *rig, vfo_t vfo, freq_t freq)
         }
 
         HAMLIB_TRACE;
+
+        if (band_changing) { rig_band_changed(rig, curr_band); }
+
         retcode = caps->set_freq(rig, vfo, freq);
     }
 
@@ -3283,7 +3293,7 @@ int HAMLIB_API rig_get_vfo(RIG *rig, vfo_t *vfo)
 
     caps = rig->caps;
 
-    if (caps->get_vfo == NULL)
+    if (caps->get_vfo == NULL && RIG_ICOM != RIG_BACKEND_NUM(rig->caps->rig_model))
     {
         rig_debug(RIG_DEBUG_WARN, "%s: no get_vfo\n", __func__);
         ELAPSED2;
@@ -4464,7 +4474,7 @@ int HAMLIB_API rig_set_split_freq(RIG *rig, vfo_t vfo, freq_t tx_freq)
     const struct rig_caps *caps;
     const struct rig_state *rs;
     int retcode, rc2;
-    vfo_t curr_vfo, tx_vfo;
+    vfo_t curr_vfo, tx_vfo = RIG_VFO_CURR;
     freq_t tfreq = 0;
 
     ENTERFUNC2;
@@ -8718,18 +8728,22 @@ int morse_data_handler_set_keyspd(RIG *rig, int keyspd)
  */
 HAMLIB_EXPORT(void *) rig_data_pointer(RIG *rig, rig_ptrx_t idx)
 {
-  switch(idx)
+    switch (idx)
     {
     case RIG_PTRX_RIGPORT:
-      return RIGPORT(rig);
+        return RIGPORT(rig);
+
     case RIG_PTRX_PTTPORT:
-      return PTTPORT(rig);
+        return PTTPORT(rig);
+
     case RIG_PTRX_DCDPORT:
-      return DCDPORT(rig);
+        return DCDPORT(rig);
+
     case RIG_PTRX_CACHE:
-      return CACHE(rig);
+        return CACHE(rig);
+
     default:
-      rig_debug(RIG_DEBUG_ERR, "%s: Invalid data index=%d\n", __func__, idx);
-      return NULL;
+        rig_debug(RIG_DEBUG_ERR, "%s: Invalid data index=%d\n", __func__, idx);
+        return NULL;
     }
 }
diff --git a/src/sprintflst.c b/src/sprintflst.c
index a53bf30ab..1c22710af 100644
--- a/src/sprintflst.c
+++ b/src/sprintflst.c
@@ -177,6 +177,7 @@ int rig_sprintf_func(char *str, int nlen, setting_t func)
 
         if (!ms || !ms[0])
         {
+            rig_debug(RIG_EINTERNAL, "%s: unknown RIG_FUNC=%x\n", __func__, i);
             continue;    /* unknown, FIXME! */
         }