Did someone have the same problem?
Just add a synth, set Track to "off" so it sounds by itself and set a freq.
Now add another synth, even if it's not in the signal path. In my Axe, 7.06 firmware version, the pitch of synth #1 changes the moment I add the second synth. As I understand it, it shouldn't happen if the VCOs are independent.
I need to have both synths on (with two voices each), one of them with white noise, and the other playing a certain freq that I modify with my pedal (actually playing a song), and it's not possible this way.