diff --git a/apps/px4io/px4io.c b/apps/px4io/px4io.c
index 4e3555b13e..e51c1c73c1 100644
--- a/apps/px4io/px4io.c
+++ b/apps/px4io/px4io.c
@@ -51,6 +51,8 @@
 #include <drivers/drv_pwm_output.h>
 #include <drivers/drv_hrt.h>
 
+#include <stm32_uart.h>
+
 #include "px4io.h"
 
 __EXPORT int user_start(int argc, char *argv[]);
@@ -59,6 +61,8 @@ extern void up_cxxinitialize(void);
 
 struct sys_state_s 	system_state;
 
+static struct hrt_call serial_dma_call;
+
 int user_start(int argc, char *argv[])
 {
 	/* run C++ ctors before we go any further */
@@ -72,6 +76,12 @@ int user_start(int argc, char *argv[])
 	/* configure the high-resolution time/callout interface */
 	hrt_init();
 
+	/*
+	 * Poll at 1ms intervals for received bytes that have not triggered
+	 * a DMA event.
+	 */
+	hrt_call_every(&serial_dma_call, 1000, 1000, (hrt_callout)stm32_serial_dma_poll, NULL);
+
 	/* print some startup info */
 	lib_lowprintf("\nPX4IO: starting\n");
 
diff --git a/nuttx/configs/px4io/io/defconfig b/nuttx/configs/px4io/io/defconfig
index e0986b72c9..d2a4f38487 100755
--- a/nuttx/configs/px4io/io/defconfig
+++ b/nuttx/configs/px4io/io/defconfig
@@ -190,7 +190,8 @@ CONFIG_USART3_2STOP=0
 
 CONFIG_USART1_RXDMA=y
 SERIAL_HAVE_CONSOLE_DMA=y
-CONFIG_USART2_RXDMA=y
+# Conflicts with I2C1 DMA
+CONFIG_USART2_RXDMA=n
 CONFIG_USART3_RXDMA=y
 
 #