diff --git a/lib_xua/src/core/audiohub/xua_audiohub.xc b/lib_xua/src/core/audiohub/xua_audiohub.xc
index 49097a6d..7e33e16e 100755
--- a/lib_xua/src/core/audiohub/xua_audiohub.xc
+++ b/lib_xua/src/core/audiohub/xua_audiohub.xc
@@ -29,6 +29,14 @@
 #endif
 #endif
 
+#if (NUM_PDM_MICS > 0)
+#include "xua_pdm_mic.h"
+#endif 
+
+#if (AUD_TO_USB_RATIO > 1)
+#include "src.h"
+#endif
+
 #include "xua_commands.h"
 #include "xc_ptr.h"
 
@@ -36,6 +44,7 @@
 
 static unsigned samplesOut[MAX(NUM_USB_CHAN_OUT, I2S_CHANS_DAC)];
 
+/* TODO Rm me */
 #ifndef ADAT_RX
 #define ADAT_RX 0
 #endif
@@ -49,6 +58,7 @@ static unsigned samplesOut[MAX(NUM_USB_CHAN_OUT, I2S_CHANS_DAC)];
 
 static unsigned samplesIn[2][MAX(NUM_USB_CHAN_IN, IN_CHAN_COUNT)];
 
+/* TODO Rm me */
 #if defined(ADAT_RX) && (ADAT_RX ==0)
 #undef ADAT_RX
 #endif
@@ -57,10 +67,6 @@ static unsigned samplesIn[2][MAX(NUM_USB_CHAN_IN, IN_CHAN_COUNT)];
 #undef SPDIF_RX
 #endif
 
-#if (AUD_TO_USB_RATIO > 1)
-#include "src.h"
-#endif
-
 #if (DSD_CHANS_DAC != 0)
 extern buffered out port:32 p_dsd_dac[DSD_CHANS_DAC];
 extern buffered out port:32 p_dsd_clk;
@@ -1307,10 +1313,7 @@ void XUA_AudioHub(chanend ?c_mix_out
 
     /* Clock master clock-block from master-clock port */
     /* Note, marked unsafe since other cores may be using this mclk port */
-    unsafe
-    {
-        configure_clock_src(clk_audio_mclk, (port) p_mclk_in);
-    }
+    configure_clock_src(clk_audio_mclk, p_mclk_in);
 
     start_clock(clk_audio_mclk);
 
@@ -1322,24 +1325,25 @@ void XUA_AudioHub(chanend ?c_mix_out
         EnableBufferedPort(p_dsd_dac[i], 32);
     }
 #endif
+
 #ifdef ADAT_TX
     /* Share SPDIF clk blk */
-    unsafe
-    {
-        configure_clock_src(clk_mst_spd, (port)p_mclk_in);
-    }
+    configure_clock_src(clk_mst_spd, p_mclk_in);
     configure_out_port_no_ready(p_adat_tx, clk_mst_spd, 0);
     set_clock_fall_delay(clk_mst_spd, 7);
 #if (XUA_SPDIF_TX_EN == 0)
     start_clock(clk_mst_spd);
 #endif
 #endif
+    
     /* Configure ADAT/SPDIF tx ports */
 #if (XUA_SPDIF_TX_EN) && (SPDIF_TX_TILE == AUDIO_IO_TILE)
-    unsafe
-    {
-        SpdifTransmitPortConfig(p_spdif_tx, clk_mst_spd,  (port)p_mclk_in);
-    }
+    SpdifTransmitPortConfig(p_spdif_tx, clk_mst_spd, p_mclk_in);
+#endif
+
+#if (NUM_PDM_MICS > 0) && (PDM_TILE == AUDIO_IO_TILE)
+    /* Configure clocks ports - sharing mclk port with I2S */
+    xua_pdm_mic_config(p_mclk_in);
 #endif
 
     /* Perform required CODEC/ADC/DAC initialisation */
diff --git a/lib_xua/src/core/main.xc b/lib_xua/src/core/main.xc
index a3f6f4f6..9ffbb400 100755
--- a/lib_xua/src/core/main.xc
+++ b/lib_xua/src/core/main.xc
@@ -123,15 +123,7 @@ on tile[AUDIO_IO_TILE] : buffered out port:32 p_lrclk       = PORT_I2S_LRCLK;
 on tile[AUDIO_IO_TILE] : buffered out port:32 p_bclk        = PORT_I2S_BCLK;
 #endif
 
-/* Note, declared unsafe as sometimes we want to share this port
-e.g. PDM mics and I2S use same master clock IO */
-on tile[AUDIO_IO_TILE] :  port p_mclk_in_          = PORT_MCLK_IN;
-
-/* TODO p_mclk_in should be delared as an unsafe resource */
-unsafe
-{
-        unsafe port p_mclk_in;
-}
+on tile[AUDIO_IO_TILE] :  in port p_mclk_in                 = PORT_MCLK_IN;
 
 #ifndef NO_USB 
 on tile[XUD_TILE] : in port p_for_mclk_count                = PORT_MCLK_COUNT;
@@ -190,7 +182,7 @@ in port p_pdm_clk               = PORT_PDM_CLK;
 
 in buffered port:32 p_pdm_mics  = PORT_PDM_DATA;
 #if (PDM_TILE != AUDIO_IO_TILE)
-/* If Mics and I2S are on the same tile we'll share an MCLK port */
+/* If Mics and I2S are not the same tile we need a separate MCLK port */
 in port p_pdm_mclk              = PORT_PDM_MCLK;
 #endif
 #endif
@@ -363,18 +355,12 @@ VENDOR_REQUESTS_PARAMS_DEC_
             unsigned x;
             thread_speed();
 
-            /* TODO p_mclk_in should be delared as an unsafe resource */
-            unsafe
-            {
-                p_mclk_in = p_mclk_in_;
-            }
-
             /* Attach mclk count port to mclk clock-block (for feedback) */
             //set_port_clock(p_for_mclk_count, clk_audio_mclk);
 #if(AUDIO_IO_TILE != XUD_TILE)
-            set_clock_src(clk_audio_mclk2, p_mclk_in2);
-            set_port_clock(p_for_mclk_count, clk_audio_mclk2);
-            start_clock(clk_audio_mclk2);
+            set_clock_src(clk_audio_mclk_usb, p_mclk_in_usb);
+            set_port_clock(p_for_mclk_count, clk_audio_mclk_usb);
+            start_clock(clk_audio_mclk_usb);
 #else
             /* Clock port from same clock-block as I2S */
             /* TODO remove asm() */
@@ -626,11 +612,6 @@ int main()
 
         on tile[AUDIO_IO_TILE]: 
         {
-            /* TODO p_mclk_in should be delared as an unsafe resource */
-            unsafe
-            {
-                p_mclk_in = p_mclk_in_;
-            }
             usb_audio_io(c_mix_out, c_adc
 #if (XUA_SPDIF_TX_EN) && (SPDIF_TX_TILE != AUDIO_IO_TILE)
                 , c_spdif_tx
@@ -717,16 +698,12 @@ int main()
 #endif
 
 #ifndef PDM_RECORD
-#if (NUM_PDM_MICS > 0)
-
+#if (NUM_PDM_MICS > 0) && (PDM_TILE != AUDIO_IO_TILE)
+        /* PDM Mics running on a separate to AudioHub */
         on stdcore[PDM_TILE]:
         { 
-            /* TODO p_mclk_in should be delared as an unsafe resource */
-            unsafe
-            {
-                p_mclk_in = p_mclk_in_;
-            }
-            pdm_mic(c_ds_output);
+            xua_pdm_mic_config(p_mclk_pdm);
+            xua_pdm_mic(c_ds_output);
         }
 #ifdef MIC_PROCESSING_USE_INTERFACE
         on stdcore[PDM_TILE].core[0]: pdm_buffer(c_ds_output, c_pdm_pcm, i_mic_process);
diff --git a/lib_xua/src/core/pdm_mics/pdm_mic.xc b/lib_xua/src/core/pdm_mics/pdm_mic.xc
index b324bc51..1007cb42 100644
--- a/lib_xua/src/core/pdm_mics/pdm_mic.xc
+++ b/lib_xua/src/core/pdm_mics/pdm_mic.xc
@@ -25,13 +25,6 @@ extern in port p_pdm_clk;
 
 extern in buffered port:32 p_pdm_mics;
 
-#if (PDM_TILE != AUDIO_IO_TILE)
-/* If Mics and I2S are on the same tile we'll share an MCLK port */
-extern in port p_pdm_mclk;
-#else
-extern unsafe port p_mclk_in;
-#endif
-
 /* Delcared in main.xc */
 extern clock clk_pdm;
 
@@ -46,11 +39,11 @@ mic_array_frame_time_domain mic_audio[2];
 #ifdef MIC_PROCESSING_USE_INTERFACE
 [[combinable]]
 #pragma unsafe arrays
-void pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio, client mic_process_if i_mic_process)
+void xua_pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio, client mic_process_if i_mic_process)
 #else
 #pragma unsafe arrays
 [[combinable]]
-void pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio)
+void xua_pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio)
 #endif
 {
     unsigned buffer;
@@ -228,15 +221,8 @@ void pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio)
 #error MAX_FREQ > 48000 NOT CURRENTLY SUPPORTED
 #endif
 
-void pdm_mic(streaming chanend c_ds_output[2])
+void xua_pdm_mic_config(in port p_pdm_mclk)
 {
-    streaming chan c_4x_pdm_mic_0;
-#if (NUM_PDM_MICS > 4)
-    streaming chan c_4x_pdm_mic_1;
-#else
-    #define c_4x_pdm_mic_1 null
-#endif
-
     /* Mics expect a clock in the 3Mhz range, calculate the divide based on mclk */
     /* e.g. For a 48kHz range mclk we expect a 3072000Hz mic clock */
     /* e.g. For a 44.1kHz range mclk we expect a 2822400Hz mic clock */
@@ -246,19 +232,22 @@ void pdm_mic(streaming chanend c_ds_output[2])
 
     unsigned micDiv = MCLK_48/3072000;
 
-#if (PDM_TILE != AUDIO_IO_TILE)
     configure_clock_src_divide(clk_pdm, p_pdm_mclk, micDiv/2);
-#else
-    /* Sharing mclk port with I2S */
-    unsafe
-    {
-        configure_clock_src_divide(clk_pdm, (port) p_mclk_in, micDiv/2);
-    }
-#endif
+    
     configure_port_clock_output(p_pdm_clk, clk_pdm);
     configure_in_port(p_pdm_mics, clk_pdm);
     start_clock(clk_pdm);
+}
 
+void xua_pdm_mic(streaming chanend c_ds_output[2])
+{
+    streaming chan c_4x_pdm_mic_0;
+#if (NUM_PDM_MICS > 4)
+    streaming chan c_4x_pdm_mic_1;
+#else
+    #define c_4x_pdm_mic_1 null
+#endif
+  
     par
     {
         mic_array_pdm_rx(p_pdm_mics, c_4x_pdm_mic_0, c_4x_pdm_mic_1);
diff --git a/lib_xua/src/core/pdm_mics/xua_pdm_mic.h b/lib_xua/src/core/pdm_mics/xua_pdm_mic.h
index 1dcb983b..7232f3c2 100644
--- a/lib_xua/src/core/pdm_mics/xua_pdm_mic.h
+++ b/lib_xua/src/core/pdm_mics/xua_pdm_mic.h
@@ -1,7 +1,12 @@
 // Copyright (c) 2015-2018, XMOS Ltd, All rights reserved
 
+/* Included from lib_mic_array */
 #include "mic_array.h"
 
+
+/* Configures PDM ports/clocks */
+void xua_pdm_mic_config(in port p_mclk_pdm);
+
 #ifdef MIC_PROCESSING_USE_INTERFACE
 /* Interface based user processing */
 typedef interface mic_process_if
@@ -12,7 +17,7 @@ typedef interface mic_process_if
 
 
 [[combinable]]
-void pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio
+void xua_pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio
 #ifdef MIC_PROCESSING_USE_INTERFACE
    , client mic_process_if i_mic_process
 #endif
@@ -22,7 +27,7 @@ void pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio
 void user_pdm_process(server mic_process_if i_mic_data);
 
 /* PDM interface and decimation cores */
-void pdm_mic(streaming chanend c_ds_output[2]);
+void xua_pdm_mic(streaming chanend c_ds_output[2]);
 
 #else
 
@@ -33,10 +38,10 @@ void user_pdm_init();
 
 /* PDM interface and decimation cores */
 [[combinable]]
-void pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio);
+void xua_pdm_buffer(streaming chanend c_ds_output[2], chanend c_audio);
 
 /* PDM interface and decimation cores */
-void pdm_mic(streaming chanend c_ds_output[2]);
+void xua_pdm_mic(streaming chanend c_ds_output[2]);
 
 #endif