diff --git a/nuttx-configs/px4io-v2/nsh/defconfig b/nuttx-configs/px4io-v2/nsh/defconfig
index a9b8477948..6871908315 100755
--- a/nuttx-configs/px4io-v2/nsh/defconfig
+++ b/nuttx-configs/px4io-v2/nsh/defconfig
@@ -164,8 +164,8 @@ CONFIG_USART1_SERIAL_CONSOLE=y
 CONFIG_USART2_SERIAL_CONSOLE=n
 CONFIG_USART3_SERIAL_CONSOLE=n
 
-CONFIG_USART1_TXBUFSIZE=64
-CONFIG_USART2_TXBUFSIZE=64
+CONFIG_USART1_TXBUFSIZE=32
+CONFIG_USART2_TXBUFSIZE=32
 CONFIG_USART3_TXBUFSIZE=64
 
 CONFIG_USART1_RXBUFSIZE=64