I lost part of the PAFL bus in the middle of the performance for no reason that I could find. The PAFL bus worked perfectly up to that point. I don’t know what the cause was.

My problem was when I pushed the PAFL button on the surface for any of the Auxes and Groups, I couldn’t hear anything on the PAFL bus, though the corresponding yellow indicators on the surface lit up, though audio was routed to them, their meters were showing activity and corresponding audio was coming out of each of those busses as I expected. The phones volume knob on the surface was fully clockwise. Pushing the Output AFL and Input AFL buttons made no changes. I browsed through the PAFL settings and I couldn’t find any explanation. However, I could hear any and all of the inputs on the PAFL buss as I expected. The problem apparently was within theses busses.

Just to see what would happen, I pushed the SEL button on the surface of an Aux bus. I pushed and held the SEL button on the surface for a processing stage (I chose the parametric EQ). Audio re-appeared on the PAFL bus. Suddenly, PAFL worked properly for all Aux and Group busses, as if something was jarred back into place.

I could not recreate my problem.

Surface is T112 and dual mix racks of iDR48 and iDR32. Firmware 1.70.

Any thoughts?