diff --git a/lib_xua/src/core/clocking/clockgen.xc b/lib_xua/src/core/clocking/clockgen.xc
index c2264738..b06a5250 100644
--- a/lib_xua/src/core/clocking/clockgen.xc
+++ b/lib_xua/src/core/clocking/clockgen.xc
@@ -40,10 +40,10 @@ static int clockInt[NUM_CLOCKS];                            /* Interupt flag for
 static int clockId[NUM_CLOCKS];
 
 [[combinable]]
-void PllRefPinTask(server interface sync_if i_sync, out port p_sync)
+void PllRefPinTask(server interface sync_if i_sync, out port p_pll_ref)
 {
     static unsigned pinVal= 0;
-    p_sync <: pinVal;
+    static unsigned short pinTime = 0;
 
     while(1)
     {
@@ -51,7 +51,30 @@ void PllRefPinTask(server interface sync_if i_sync, out port p_sync)
         {
             case i_sync.toggle():
                 pinVal = ~pinVal;
-                 p_sync <: pinVal;
+                 p_pll_ref <: pinVal;
+                break;
+            
+            case i_sync.init():
+                p_pll_ref <: pinVal @ pinTime;
+                pinTime += (unsigned short)(LOCAL_CLOCK_INCREMENT - (LOCAL_CLOCK_INCREMENT/2));
+                p_pll_ref @ pinTime <: pinVal;
+                break;
+
+            case i_sync.toggle_timed(int relative):
+                
+                if (!relative)
+                {   
+                    pinTime += (short) LOCAL_CLOCK_INCREMENT;
+                    pinVal = !pinVal;
+                    p_pll_ref @ pinTime <: pinVal;
+                }
+                else
+                {
+                    p_pll_ref <: pinVal @ pinTime;
+                    pinTime += (short) LOCAL_CLOCK_INCREMENT;
+                    pinVal = !pinVal;
+                    p_pll_ref @ pinTime <: pinVal;
+                }
                 break;
         }
     }
@@ -218,12 +241,19 @@ extern int samples_to_host_inputs_buff[NUM_USB_CHAN_IN];
 int VendorAudCoreReqs(unsigned cmd, chanend c);
 
 #pragma unsafe arrays
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
 void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, out port p, chanend c_dig_rx, chanend c_clk_ctl, chanend c_clk_int)
+#else
+void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, client interface sync_if i_sync, chanend c_dig_rx, chanend c_clk_ctl, chanend c_clk_int)
+#endif
 {
     timer t_local;
     unsigned timeNextEdge, timeLastEdge, timeNextClockDetection;
+
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
     unsigned pinVal = 0;
     unsigned short  pinTime;
+#endif
     unsigned clkMode = CLOCK_INTERNAL;              /* Current clocking mode in operation */
     unsigned tmp;
 
@@ -325,10 +355,15 @@ void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, out port p, ch
     outuint(c_dig_rx, 1);
 #endif
 
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
     /* Initial ref clock output and get timestamp */
     p <: pinVal @ pinTime;
     pinTime += (unsigned short)(LOCAL_CLOCK_INCREMENT - (LOCAL_CLOCK_INCREMENT/2));
     p @ pinTime <: pinVal;
+#else
+    /* TODO ideally always use interface */
+    i_sync.init();
+#endif
 
     while(1)
     {
@@ -451,11 +486,15 @@ void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, out port p, ch
             /* Generate local clock from timer */
             case t_local when timerafter(timeNextEdge) :> void:
 
-
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
                 /* Setup next local clock edge */
                 pinTime += (short) LOCAL_CLOCK_INCREMENT;
                 pinVal = !pinVal;
                 p @ pinTime <: pinVal;
+#else
+                /* TODO ideally always use interface */
+                i_sync.toggle_timed(0);
+#endif
 
                 /* Record time of edge */
                 timeLastEdge = timeNextEdge;
@@ -584,11 +623,16 @@ void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, out port p, ch
                             /* Setup for next edge */
                             timeNextEdge = spdifReceivedTime + LOCAL_CLOCK_INCREMENT + LOCAL_CLOCK_MARGIN;
 
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
                             /* Toggle edge */
                             p <: pinVal @ pinTime;
                             pinTime += (short) LOCAL_CLOCK_INCREMENT;
                             pinVal = !pinVal;
                             p @ pinTime <: pinVal;
+#else
+                            i_sync.toggle_timed(1);
+
+#endif
 
                             /* Reset counters */
                             spdifCounters.receivedSamples = 0;
@@ -693,12 +737,15 @@ void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, out port p, ch
                                             /* Setup for next edge */
                                             timeNextEdge = adatReceivedTime + LOCAL_CLOCK_INCREMENT + LOCAL_CLOCK_MARGIN;
 
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
                                             /* Toggle edge */
                                             p <: pinVal @ pinTime;
                                             pinTime += LOCAL_CLOCK_INCREMENT;
                                             pinVal = !pinVal;
                                             p @ pinTime <: pinVal;
-
+#else
+                                            i_sync.toggle_timed(1);
+#endif
                                             /* Reset counters */
                                             adatCounters.receivedSamples = 0;
 
diff --git a/lib_xua/src/core/clocking/clocking.h b/lib_xua/src/core/clocking/clocking.h
index a388f16a..d892160d 100644
--- a/lib_xua/src/core/clocking/clocking.h
+++ b/lib_xua/src/core/clocking/clocking.h
@@ -4,6 +4,18 @@
 #ifndef _CLOCKING_H_
 #define _CLOCKING_H_
 
+
+
+interface sync_if
+{
+    void toggle();
+    void init();
+    void toggle_timed(int relative);
+};
+
+[[combinable]]
+void PllRefPinTask(server interface sync_if i_sync, out port p_sync);
+
 /** Clock generation and digital audio I/O handling.
  *
  *  \param c_spdif_rx channel connected to S/PDIF receive thread
@@ -15,14 +27,10 @@
  *  \param c_clk_int channel connected to the decouple() thread for clock
                      interrupts
  */
-void clockGen (streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, out port p, chanend c_audio, chanend c_clk_ctl, chanend c_clk_int);
-
-interface sync_if
-{
-    void toggle();
-};
-
-[[combinable]]
-void PllRefPinTask(server interface sync_if i_sync, out port p_sync);
+#if (AUDIO_IO_TILE == PLL_REF_TILE)
+void clockGen(streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, client interface out port p_pll_ref, chanend c_audio, chanend c_clk_ctl, chanend c_clk_int);
+#else
+void clockGen(streaming chanend ?c_spdif_rx, chanend ?c_adat_rx, client interface sync_if i_sync, chanend c_audio, chanend c_clk_ctl, chanend c_clk_int);
+#endif
 #endif
 
diff --git a/lib_xua/src/core/main.xc b/lib_xua/src/core/main.xc
index d6264a60..a3aa94cf 100755
--- a/lib_xua/src/core/main.xc
+++ b/lib_xua/src/core/main.xc
@@ -432,6 +432,9 @@ void usb_audio_io(chanend ?c_aud_in,
 #endif
     , chanend c_pdm_pcm
 #endif
+#if (XUA_SPDIF_RX_EN && (AUDIO_IO_TILE != PLL_REF_TILE))
+    , client interface sync_if i_sync
+#endif
 )
 {
 #ifdef MIXER
@@ -503,9 +506,13 @@ void usb_audio_io(chanend ?c_aud_in,
 
 #if (XUA_SPDIF_RX_EN || ADAT_RX)
         {
+            /* ClockGen must currently run on same tile as AudioHub due to shared memory buffer */
             thread_speed();
-
+#if AUDIO_IO_TILE == PLL_REF_TILE
             clockGen(c_spdif_rx, c_adat_rx, p_pll_ref, c_dig_rx, c_clk_ctl, c_clk_int);
+#else
+            clockGen(c_spdif_rx, c_adat_rx, i_sync, c_dig_rx, c_clk_ctl, c_clk_int);
+#endif    
         }
 #endif
 
@@ -583,7 +590,7 @@ int main()
 #endif
 #endif
 
-#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC)
+#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC) || (XUA_SPDIF_RX_EN && (AUDIO_IO_TILE != PLL_REF_TILE))
     interface sync_if i_sync;
 #endif
 
@@ -593,9 +600,8 @@ int main()
     {
         USER_MAIN_CORES
 
-#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC)
+#if (XUA_SYNCMODE == XUA_SYNCMODE_SYNC) || (XUA_SPDIF_RX_EN && (AUDIO_IO_TILE != PLL_REF_TILE))
         on tile[PLL_REF_TILE]: PllRefPinTask(i_sync, p_pll_ref);
-
 #endif
         on tile[XUD_TILE]:
         par
@@ -649,6 +655,9 @@ int main()
                 , c_ds_output
 #endif
                 , c_pdm_pcm
+#endif
+#if (XUA_SPDIF_RX_EN && (AUDIO_IO_TILE != PLL_REF_TILE))
+                , i_sync
 #endif
             );
         }