Strange Behavior in Sound Engine?

[MaF]

Can anyone reproduce or explain the following?

Make both OSCs Classic
Tune OSC 2 to -36
turn FM to max
switch on Sync

Now play with the WT Index of OSC 1. When you switch from Saw98% (coming from the Sine Wave) to Saw100% the wave itself only changes a very little, of course. The sound, however, much more than expected. This also happens when OSC 1 is wavetable. At any WT index of OSC1 the sound transition is smooth but in the middle.

cheers
MaF