Both V and M-Bot are looking at Serph, now; M-Bot tilts, and V's distorted muzzle is easier to interpret as confused in comparison.

Instead, since they can both understand what Serph said, M-Bot tries to hum a note - a distinct pitch...

One that, with some effort, V matches. Their voice is deeper, in this form - but if this will somehow help them change again, they feel they can't not try.