Mtr ignores --interface and --address if used with mwan3


I wanted to diagnose some packetloss on one of my wan links. I have 3 uplinks and use mwan3 to manage them.

Ping -I ethX dst

does work and uses the interface i do specify.

mtr -I ethX dst

does not work and it uses instead the default route.

Is this a bug that should be reported here or is this upstream or am I stupid and just miss parameter to make this work?

Thanks for hints