diff --git a/nuttx-configs/px4fmu-v4/nsh/defconfig b/nuttx-configs/px4fmu-v4/nsh/defconfig
index f4533279d4..597f87c851 100644
--- a/nuttx-configs/px4fmu-v4/nsh/defconfig
+++ b/nuttx-configs/px4fmu-v4/nsh/defconfig
@@ -552,7 +552,7 @@ CONFIG_UART7_SERIAL_CONSOLE=y
 # USART1 Configuration
 #
 CONFIG_USART1_RXBUFSIZE=600
-CONFIG_USART1_TXBUFSIZE=2000
+CONFIG_USART1_TXBUFSIZE=4000
 CONFIG_USART1_BAUD=115200
 CONFIG_USART1_BITS=8
 CONFIG_USART1_PARITY=0
@@ -667,7 +667,7 @@ CONFIG_CDCACM_NWRREQS=4
 CONFIG_CDCACM_NRDREQS=4
 CONFIG_CDCACM_BULKIN_REQLEN=96
 CONFIG_CDCACM_RXBUFSIZE=600
-CONFIG_CDCACM_TXBUFSIZE=4000
+CONFIG_CDCACM_TXBUFSIZE=8000
 CONFIG_CDCACM_VENDORID=0x26ac
 CONFIG_CDCACM_PRODUCTID=0x0012
 CONFIG_CDCACM_VENDORSTR="3D Robotics"