I'm a new Kemper owner, still getting familiar with everything so this very well could be me just not being familiar with the Powerhead yet. The past two times I have played it, the unit has been lagging and the sound coming out is similar to a volume swell using the guitar volume knob. The sound starts soft and then peaks, all in about half second or a little less. I've tried multiple profiles including the factory loaded and purchased TJ profiles, monitor out, guitar cabinet out, and changing guitars and it is consistent across all I have tried. Are there any settings I should be looking at that may be causing this?
Check compressor settings in amp section and / or stomp box ( if any )
Sounds like your input noise gate is set too high. Maybe check it? Good luck.
Do you have any FX locked? If the problem is on all profiles it must be either an effect that is on all the time or an Input or Output menu setting.
You may have enabled the Delay/Rev output instead of the Master Mono or Master Stereo out. That could explain the delay and apparent swell.