diff --git a/lib_xua/api/xua_buffer.h b/lib_xua/api/xua_buffer.h
index d7d182d7..b9f8e56b 100644
--- a/lib_xua/api/xua_buffer.h
+++ b/lib_xua/api/xua_buffer.h
@@ -81,7 +81,7 @@ void XUA_Buffer_Ep(chanend c_aud_out,
 #ifdef CHAN_BUFF_CTRL
             , chanend c_buff_ctrl
 #endif
-#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC) || defined(__DOXYGEN__)
+#if ((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) && !XUA_USE_APP_PLL) || defined(__DOXYGEN__)
             , client interface pll_ref_if i_pll_ref
 #endif
         );
diff --git a/lib_xua/src/core/buffer/ep/ep_buffer.xc b/lib_xua/src/core/buffer/ep/ep_buffer.xc
index 2aa2218e..d4c1776d 100644
--- a/lib_xua/src/core/buffer/ep/ep_buffer.xc
+++ b/lib_xua/src/core/buffer/ep/ep_buffer.xc
@@ -358,16 +358,17 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
 #ifndef LOCAL_CLOCK_MARGIN
 #define LOCAL_CLOCK_MARGIN          (1000)
 #endif
+
+#if (XUA_USE_APP_PLL)
+    struct PllSettings pllSettings;
+    AppPllGetSettings(DEFAULT_MCLK, pllSettings);
+#else
     timer t_sofCheck;
     unsigned timeLastEdge;
     unsigned timeNextEdge;
     t_sofCheck :> timeLastEdge;
     timeNextEdge + LOCAL_CLOCK_INCREMENT;
     i_pll_ref.toggle();
-
-#if (XUA_USE_APP_PLL)
-    struct PllSettings pllSettings;
-    AppPllGetSettings(DEFAULT_MCLK, pllSettings);
 #endif
 
 #endif
@@ -520,7 +521,7 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
                 }
                 break;
             }
-#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC)
+#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC) && (!XUA_USE_APP_PLL)
             case t_sofCheck when timerafter(timeNextEdge) :> void:
                 i_pll_ref.toggle();
                 timeLastEdge = timeNextEdge;
@@ -550,12 +551,14 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
                 sofCount += 1000;
                 if (sofCount == framesPerSec)
                 {
+                    sofCount = 0;
+                    pllUpdate++;
+#if (!XUA_USE_APP_PLL)
                     /* Port is accessed via interface to allow flexibilty with location */
                     i_pll_ref.toggle();
                     t_sofCheck :> timeLastEdge;
-                    sofCount = 0;
                     timeNextEdge = timeLastEdge + LOCAL_CLOCK_INCREMENT + LOCAL_CLOCK_MARGIN;
-                    pllUpdate++;
+#endif
                 }
 #if (XUA_USE_APP_PLL)
                 // Update PLL @ 100Hz
@@ -671,7 +674,6 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
                         clockcounter = 0;
                     }
 #else
-
                     /* Assuming 48kHz from a 24.576 master clock (0.0407uS period)
                      * MCLK ticks per SOF = 125uS / 0.0407 = 3072 MCLK ticks per SOF.
                      * expected Feedback is 48000/8000 = 6 samples. so 0x60000 in 16:16 format.
@@ -922,8 +924,8 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
 #endif
 #endif
 
-#if XUA_HID_ENABLED
-                /* HID Report Data */
+#if (XUA_HID_ENABLED)
+            /* HID Report Data */
             case XUD_SetData_Select(c_hid, ep_hid, result):
                 hid_ready_flag = 0U;
                 unsigned reportTime;
@@ -936,7 +938,7 @@ void XUA_Buffer_Ep(register chanend c_aud_out,
 #endif
 
 #ifdef MIDI
-                /* Received word from MIDI thread - Check for ACK or Data */
+            /* Received word from MIDI thread - Check for ACK or Data */
             case midi_get_ack_or_data(c_midi, is_ack, datum):
                 if (is_ack)
                 {
diff --git a/lib_xua/src/core/main.xc b/lib_xua/src/core/main.xc
index 1e2a5145..711afbce 100755
--- a/lib_xua/src/core/main.xc
+++ b/lib_xua/src/core/main.xc
@@ -145,7 +145,7 @@ on stdcore[XUD_TILE] : buffered in port:32 p_adat_rx        = PORT_ADAT_IN;
 on tile[XUD_TILE] : in port p_spdif_rx                      = PORT_SPDIF_IN;
 #endif
 
-#if (XUA_SPDIF_RX_EN) || (XUA_ADAT_RX_EN) || (XUA_SYNCMODE == XUA_SYNCMODE_SYNC)
+#if (XUA_SPDIF_RX_EN) || (XUA_ADAT_RX_EN) || ((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) && (!XUA_USE_APP_PLL))
 /* Reference to external clock multiplier */
 on tile[PLL_REF_TILE] : out port p_pll_ref                  = PORT_PLL_REF;
 #endif
@@ -467,7 +467,7 @@ int main()
 #endif
 #endif
 
-#if ((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) || XUA_SPDIF_RX_EN || XUA_ADAT_RX_EN)
+#if (((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) && !XUA_USE_APP_PLL) || XUA_SPDIF_RX_EN || XUA_ADAT_RX_EN)
     interface pll_ref_if i_pll_ref;
 #endif
     chan c_sof;
@@ -491,7 +491,7 @@ int main()
     {
         USER_MAIN_CORES
 
-#if ((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) || XUA_SPDIF_RX_EN || XUA_ADAT_RX_EN)
+#if (((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) && XYA_USE_APP_PLL) || XUA_SPDIF_RX_EN || XUA_ADAT_RX_EN)
         on tile[PLL_REF_TILE]: PllRefPinTask(i_pll_ref, p_pll_ref);
 #endif
         on tile[XUD_TILE]:
@@ -563,7 +563,7 @@ int main()
                            , c_xud_in[ENDPOINT_NUMBER_IN_HID]
 #endif
                            , c_mix_out
-#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC)
+#if ((XUA_SYNCMODE == XUA_SYNCMODE_SYNC) && (!XUA_USE_APP_PLL))
                            , i_pll_ref
 #endif
                     );