diff --git a/lib_xua/src/core/buffer/decouple/decouple.xc b/lib_xua/src/core/buffer/decouple/decouple.xc
index 668af697..2e64ecd0 100644
--- a/lib_xua/src/core/buffer/decouple/decouple.xc
+++ b/lib_xua/src/core/buffer/decouple/decouple.xc
@@ -68,18 +68,18 @@ static xc_ptr p_multIn;
 #endif
 
 #if (AUDIO_CLASS == 2)
-unsigned g_numUsbChan_In = NUM_USB_CHAN_IN; /* Number of channels to/from the USB bus - initialised to HS for UAC2.0 */
-unsigned g_numUsbChan_Out = NUM_USB_CHAN_OUT;
-unsigned g_curSubSlot_Out = HS_STREAM_FORMAT_OUTPUT_1_SUBSLOT_BYTES;
-unsigned g_curSubSlot_In  = HS_STREAM_FORMAT_INPUT_1_SUBSLOT_BYTES;
+int g_numUsbChan_In = NUM_USB_CHAN_IN; /* Number of channels to/from the USB bus - initialised to HS for UAC2.0 */
+int g_numUsbChan_Out = NUM_USB_CHAN_OUT;
+int g_curSubSlot_Out = HS_STREAM_FORMAT_OUTPUT_1_SUBSLOT_BYTES;
+int g_curSubSlot_In  = HS_STREAM_FORMAT_INPUT_1_SUBSLOT_BYTES;
 int sampsToWrite = DEFAULT_FREQ/8000;  /* HS assumed here. Expect to be junked during a overflow before stream start */
 int totalSampsToWrite = DEFAULT_FREQ/8000;
 int g_maxPacketSize = MAX_DEVICE_AUD_PACKET_SIZE_IN_HS; /* IN packet size. Init to something sensible, but expect to be re-set before stream start */
 #else
-unsigned g_numUsbChan_In = NUM_USB_CHAN_IN_FS; /* Number of channels to/from the USB bus - initialised to FS for UAC1.0 */
-unsigned g_numUsbChan_Out = NUM_USB_CHAN_OUT_FS;
-unsigned g_curSubSlot_Out = FS_STREAM_FORMAT_OUTPUT_1_SUBSLOT_BYTES;
-unsigned g_curSubSlot_In  = FS_STREAM_FORMAT_INPUT_1_SUBSLOT_BYTES;
+int g_numUsbChan_In = NUM_USB_CHAN_IN_FS; /* Number of channels to/from the USB bus - initialised to FS for UAC1.0 */
+int g_numUsbChan_Out = NUM_USB_CHAN_OUT_FS;
+int g_curSubSlot_Out = FS_STREAM_FORMAT_OUTPUT_1_SUBSLOT_BYTES;
+int g_curSubSlot_In  = FS_STREAM_FORMAT_INPUT_1_SUBSLOT_BYTES;
 int sampsToWrite = DEFAULT_FREQ/1000;  /* FS assumed here. Expect to be junked during a overflow before stream start */
 int totalSampsToWrite = DEFAULT_FREQ/1000;
 int g_maxPacketSize = MAX_DEVICE_AUD_PACKET_SIZE_IN_FS;  /* IN packet size. Init to something sensible, but expect to be re-set before stream start */
@@ -459,7 +459,7 @@ __builtin_unreachable();
             packState = 0;
 
             /* Write last packet length into FIFO */
-            unsigned datasize = totalSampsToWrite * g_curSubSlot_In * g_numUsbChan_In;
+            int datasize = totalSampsToWrite * g_curSubSlot_In * g_numUsbChan_In;
 
             GET_SHARED_GLOBAL(wrPtr, g_aud_to_host_wrptr);
             write_via_xc_ptr(wrPtr, datasize);
@@ -515,7 +515,6 @@ __builtin_unreachable();
                 GET_SHARED_GLOBAL(sampFreq, g_freqChange_sampFreq);
                 int min, mid, max;
                 GetADCCounts(sampFreq, min, mid, max);
-                
                 const int max_pkt_size = ((max * g_curSubSlot_In * g_numUsbChan_In + 3) & ~0x3) + 4;
                 int rdPtr;
                 GET_SHARED_GLOBAL(rdPtr, g_aud_to_host_rdptr);