diff --git a/nuttx-configs/px4-stm32f4discovery/nsh/defconfig b/nuttx-configs/px4-stm32f4discovery/nsh/defconfig
index 4bfb7fac86..f18fea1fdf 100644
--- a/nuttx-configs/px4-stm32f4discovery/nsh/defconfig
+++ b/nuttx-configs/px4-stm32f4discovery/nsh/defconfig
@@ -934,7 +934,7 @@ CONFIG_CDCACM_NRDREQS=4
 CONFIG_CDCACM_NWRREQS=4
 CONFIG_CDCACM_BULKIN_REQLEN=96
 CONFIG_CDCACM_RXBUFSIZE=600
-CONFIG_CDCACM_TXBUFSIZE=8000
+CONFIG_CDCACM_TXBUFSIZE=2000
 CONFIG_CDCACM_VENDORID=0x26ac
 CONFIG_CDCACM_PRODUCTID=0x0001
 CONFIG_CDCACM_VENDORSTR="3D Robotics"