Virus C question

[Timo]

With the INIT patch, aren't both oscillators used?

They're each freely running (ie. not forced to sync' as standard), so you'll have slight phasing differences when they're mixed together.
They may also be emulating the unstable/varying pitches of their analogue predecessors. It's like they're very subtly detuned. This is the "modulation" you'll hear. I think there is an option somewhere to turn off this emulated instability of the oscillators.