diff --git a/src/dma/dma.c b/src/dma/dma.c
index 141b05b..391a254 100644
--- a/src/dma/dma.c
+++ b/src/dma/dma.c
@@ -242,13 +242,13 @@ static void configure(void)
 	extern void inth_dma_ae(void);
 	intc_handler(0xbc0, inth_dma_ae, 32);
 
-	/* Set interrupt priority to 3 (IPRE[15..12] for first three channels,
-	   IPRF[11..8] for last two and error gate */
+	/* Set interrupt priority to 3, except 11 for the channels that are
+	   used by the USB driver */
 	intc_priority(INTC_DMA_DEI0, 3);
 	intc_priority(INTC_DMA_DEI1, 3);
 	intc_priority(INTC_DMA_DEI2, 3);
-	intc_priority(INTC_DMA_DEI3, 3);
-	intc_priority(INTC_DMA_DEI4, 3);
+	intc_priority(INTC_DMA_DEI3, 9);
+	intc_priority(INTC_DMA_DEI4, 9);
 	intc_priority(INTC_DMA_DEI5, 3);
 	intc_priority(INTC_DMA_DADERR, 3);
 
diff --git a/src/usb/pipes.c b/src/usb/pipes.c
index 37de6f4..26e32fe 100644
--- a/src/usb/pipes.c
+++ b/src/usb/pipes.c
@@ -234,8 +234,6 @@ static void finish_round(struct transfer volatile *t, int pipe)
 	t->size -= t->flying;
 	t->flying = 0;
 
-	if(pipe) usb_log("%d left\n", t->size);
-
 	/* Account for auto-transfers */
 	if(t->used == pipe_bufsize(pipe)) t->used = 0;
 
@@ -293,9 +291,9 @@ static void write_round(struct transfer volatile *t, int pipe)
 		/* Use DMA channel 3 for D0F and 4 for D1F */
 		int channel = (ct == D0F) ? 3 : 4;
 
-		int rc = dma_transfer_async(channel, block_size, size,
+		bool ok = dma_transfer_async(channel, block_size, size,
 			t->data, DMA_INC, (void *)FIFO, DMA_FIXED, callback);
-		usb_log("dma_transfer_async: %d, bs=%d, size=%d, fifo=%d\n", rc, block_size, size, ct);
+		if(!ok) usb_log("DMA async failed on channel %d!\n", channel);
 	}
 	else
 	{
diff --git a/src/usb/usb.c b/src/usb/usb.c
index 6a53efc..119930d 100644
--- a/src/usb/usb.c
+++ b/src/usb/usb.c
@@ -85,8 +85,8 @@ static void hpoweron_write(void)
 	USB.SYSCFG.SCKE = 1;
 	for(int i = 0; i < 10; i++) __asm__ volatile("nop");
 
-	/* Set BUSWAIT to a safe value, hopefully avoiding overlock problems */
-	USB.BUSWAIT.word = 15;
+	/* Set BUSWAIT to a safe value */
+	USB.BUSWAIT.word = 5;
 }
 
 static void hpoweroff(void)
@@ -170,7 +170,7 @@ int usb_open(usb_interface_t const **interfaces, gint_call_t callback)
 	USB.BEMPENB.word = 0x0000;
 
 	intc_handler_function(0xa20, GINT_CALL(usb_interrupt_handler));
-	intc_priority(INTC_USB, 15);
+	intc_priority(INTC_USB, 8);
 
 	return 0;
 }
diff --git a/src/usb/usb_private.h b/src/usb/usb_private.h
index 4590fa1..9b8027a 100644
--- a/src/usb/usb_private.h
+++ b/src/usb/usb_private.h
@@ -8,6 +8,7 @@
 #include <gint/defs/attributes.h>
 #include <gint/timer.h>
 #include <gint/gint.h>
+#include <gint/usb.h>
 
 //---
 // Configuration of the communication surface between module and host