Don’t think this has been mentioned, certainly couldn’t find it with a search, but apologies if there is a thread somewhere.
Take a blank 16 step Pattern. Choose any track & place 16 Trigs. Now P.lock anything you want on each step, different sample, filter setting, delay whatever.
Now whilst holding one of the Trigs down hit the corresponding Pad.
Pad plays the lock not the default sound!
Choose a different step & the Pad plays that lock instead.
Trig from an external sequencer does the same. Plays default until you hold down a P.lock step.
Now this is where it gets really weird!
Choose a different Track, anyone will do & hold down any step whilst hitting the ‘same’ Pad as before. Strange, the lock still sounds even though you’re holding a step on a different Track!!!
Incidentally the A4 displays similar behaviour only it doesn’t migrate across tracks. Hold down a locked step & play the mini keyboard, great way to audition Plocks!
I guess by holding the Trig button down you’re accessing areas that relate to Scenes or Performance param?