Yes, the two buttons use different randomization algorithms. The main randomization follows the pattern/sounds/all scopes, the overall complexity, and the genre selection algorithms (if enabled). The tab-specific randomization is triggered using the small dice icon available on each tab.
So I’ll have to deactivate pitch randomization when using the big orange button and do the pitch randomization separately when driving external sound modules via the Playbeat 4 MIDI.
I think that’s different than it was in Playbeat 3.