I got the pbf4 on monday 25.03. and works like a charm with abketon and bitwig. The day later i heard a cracking sound from my speakers. Firsrt tought was something is wrong with my souncard. Than I unplugd the pbf4 usb conector and the cracking sound was gone. Than I conect again the pbf4 and the cracking sound was back. I traid all my usb hubs another cabels but nothing changes. I have the pbf4 like a 2 days. I think I Return it
This sounds like a ground issue with your system - I don’t know why this could happen, but it’s unlikely that Grid could make a huge impact here.