diff --git a/Projects/USBtoSerial/USBtoSerial.c b/Projects/USBtoSerial/USBtoSerial.c
index 9189868835676180a6a0e1ba4700bc63bd3b14fc..145047cbc44b6e10fc02b49b22fb3ea9bb974a3f 100644
--- a/Projects/USBtoSerial/USBtoSerial.c
+++ b/Projects/USBtoSerial/USBtoSerial.c
@@ -124,8 +124,8 @@ void SetupHardware(void)
 	LEDs_Init();
 	USB_Init();
 
-	/* Configure the UART flush timer - run at Fcpu/1024 for maximum interval before overflow */
-	TCCR0B = ((1 << CS02) | (1 << CS00));
+	/* Start the flush timer so that overflows occur rapidly to push received bytes to the USB interface */
+	TCCR0B = (1 << CS02);
 }
 
 /** Event handler for the library USB Connection event. */
diff --git a/Projects/XPLAINBridge/Lib/SoftUART.c b/Projects/XPLAINBridge/Lib/SoftUART.c
index 90c23b71d4ebb61e0b6e7a8d8f5252cc34c3df61..4ec8dcdc8c5d9525d8f32c3a78927390ebe36ff1 100644
--- a/Projects/XPLAINBridge/Lib/SoftUART.c
+++ b/Projects/XPLAINBridge/Lib/SoftUART.c
@@ -124,7 +124,7 @@ ISR(TIMER1_COMPA_vect, ISR_BLOCK)
 }
 
 /** ISR to manage the transmission of bits via the software UART. */
-ISR(TIMER3_COMPA_vect, ISR_NOBLOCK)
+ISR(TIMER3_COMPA_vect, ISR_BLOCK)
 {
 	/* Check if transmission has finished */
 	if (TX_BitsRemaining)