PPM+UART: Priority to UART on HW6?

Hello guys,

This might be straightforward but it seems we can't figure this out on VESC 6.

We have a custom app that commands the VESC through UART, but we need to switch between PPM and UART.
On VESC 4, we can get PPM+UART and we can drive the motors with both inputs (no need to change APP), but for VESC 6, if PPM+UART is selected, PPM works well but UART just jitters the motors and they don't spin. 

Just as test, we changed ADC+UART, and UART commands go through on VESC6. 

Any inputs you guys can give to us? We manage to do "change APP" with arduino, but we would like to know if this PPM+UART can drive motors with both inputs without changing APP, or if PPM=0 will stop UART from moving the motors everytime.

Let  us know. Thank you!