no notification for M600

[TylonHH]

Hi,
I'm using a filament runout sensor wich works fine as it's use the M600 command. But when the printer detects a "filament change" I dont get the notification. I see in the terminal
Recv: echo:enqueueing "M600"
When I send via termianl manualy the M600 command I git the notification. So I guess it must be something how the M600 is send to the printer?! How can I solve this?
The runout sensor is configured in the marlin firmware.
Cheers

[TylonHH]

This is what I see in the Terminal when I send "by hand"
Send: N467 M600*32