diff --git a/boards/px4/fmu-v6x/nuttx-config/nsh/defconfig b/boards/px4/fmu-v6x/nuttx-config/nsh/defconfig
index edb5e8a0d8..a38915d99f 100644
--- a/boards/px4/fmu-v6x/nuttx-config/nsh/defconfig
+++ b/boards/px4/fmu-v6x/nuttx-config/nsh/defconfig
@@ -291,8 +291,9 @@ CONFIG_UART4_RXBUFSIZE=600
 CONFIG_UART4_TXBUFSIZE=1500
 CONFIG_UART5_IFLOWCONTROL=y
 CONFIG_UART5_OFLOWCONTROL=y
+CONFIG_UART7_RXBUFSIZE=1500
 CONFIG_UART5_RXDMA=y
-CONFIG_UART5_TXBUFSIZE=3000
+CONFIG_UART5_TXBUFSIZE=10000
 CONFIG_UART5_TXDMA=y
 CONFIG_UART7_BAUD=57600
 CONFIG_UART7_IFLOWCONTROL=y