Cant send commands bei UART - Up2stream pro V3

Hey Guys!

I am trying since some time with an Up2Stream pro v3. I love this device, and since yesterday i am playing with the UART-commands.

I can receive the commands which the V3 sends very well, like when it is booting, changing the source by button or in NET-mode sending the track information.

But unfortunately i cand send commands to the V3.

I am using a small CP2102 USB-UART converter connected to the RX/TX-pins of the V3. Receiving works well. When i connect RX and TX of the CP2102 i can see what i write in the command line (PuTTY).

But when i write commmands like STA; or VER; or even SRC:BT; nothing happens.

Configs in Putty are 115200baud,8,N,1, no flow control.

Can you please help me or give me some clues where i made my mistake?

Thanks!
Best greetings and 73,
Chris DC2SV

I was still trying, when i send the commands with the serial monitor of the Arduino environment, it works fine.

So, actually it seems like its a problem of Putty.