diff --git a/nuttx-configs/px4flow-v2/bootloader/defconfig b/nuttx-configs/px4flow-v2/bootloader/defconfig
index f3722ce358..4932fde6ee 100644
--- a/nuttx-configs/px4flow-v2/bootloader/defconfig
+++ b/nuttx-configs/px4flow-v2/bootloader/defconfig
@@ -620,6 +620,7 @@ CONFIG_FDCLONE_STDIO=y
 CONFIG_SDCLONE_DISABLE=y
 CONFIG_NFILE_DESCRIPTORS=0
 CONFIG_NFILE_STREAMS=0
+CONFIG_STDIO_DISABLE_BUFFERING=y
 CONFIG_NAME_MAX=0
 # CONFIG_PRIORITY_INHERITANCE is not set
 
@@ -827,7 +828,7 @@ CONFIG_SYMTAB_ORDEREDBYNAME=y
 #
 # Standard C Library Options
 #
-CONFIG_STDIO_BUFFER_SIZE=64
+# CONFIG_STDIO_BUFFER_SIZE is not set
 # CONFIG_STDIO_LINEBUFFER is not set
 CONFIG_NUNGET_CHARS=0
 # CONFIG_LIBC_DLLFCN is not set