Power-rack: no sound, vol knob won't turn up

    Hey everyone!


    My powerrack is a welcome tool! When it works it's awesome. However, I have experienced on a couple of occasions that there is no output - or well, no sound comes out of my cabinet. That is problem number 1 (it might relate to problem number 2). Here's the setup:
    A) I plug my engl vintage 30 4x12 into the poweramp out on the kemper (I have checked that vol is up, and that the poweramp i turned on)
    B) I tune the guitar and check there is signal going in - and when I strum the guitar, the output LED lights up.
    C) I go to browser mode and start to play
    D) Nothing happens. No sound.
    I've checked all cables are good, all connections are good, there are no muted signals and volume is up. When i run into this problem, I have to turn if off and wait 5-10 minuttes - and then sometimes I will have an output sound again.


    It might relate to the second problem: if I need to turn up the master volume, the setting will flick back and forth and won't stay any specifik setting. I have experienced that sometimes I can turn it up very slowly, and it seems to work better. Often, the sound will increase dramatically within a few minuttes after I set and lock a volume level (having been lower than expected on that setting). For example: I put the master vol to 5.6 - and this will be a good volume in the rehearsal room. But sometimes it just doesn't get to that level - and I turn it up to say 7.5 - without the volume actually increasing. After a few mins of playing, it'll come in full throttle though.


    Does anyone have any idea what might be causing this?


    NB: a third problem is that whenever I switch between rigs, it takes a full second or so before it actually changed (the prior rig "bleeds" into the newly choosen). Kinda annoying if you have to change from metal to clean in an instant...any advice?


    I hope this is understandable - please let me know if I need to clarify anything.! Thanks in advance!



    I had this happen on a new unit with the master volume knob. If I rotated the master volume knob slowly there was a section of the knob that was really flakey. The volume would skip around and move by itself, sometimes the values would move but the actual volume wouldn't change...I tried restoring firmware, rebooting, etc, I couldn't figure it out so I returned it for a new one. New one works perfectly.

    Quote from delichef

    I had this happen on a new unit with the master volume knob. If I rotated the master volume knob slowly there was a section of the knob that was really flakey. The volume would skip around and move by itself, sometimes the values would move but the actual volume wouldn't change...I tried restoring firmware, rebooting, etc, I couldn't figure it out so I returned it for a new one. New one works perfectly.

    That appears to be my problem. Strangely enough it happens only when the band is playing - it has never happened while I sat with it by myself...


    Tryonova: I am using a Behringer midi board - the (in)famous FCB1010. I figure that might cause the bleeding between switches.

    Quote from Ikarus_On_Fire

    That appears to be my problem. Strangely enough it happens only when the band is playing - it has never happened while I sat with it by myself...


    Hmm, that's weird. Happened every time for me. How old is your firmware? I assumed it was a bad potentiometer (don't even know if that's possible with a unit like this), but when I searched these forums it looked like people had a similar problem with some of the really old firmwares. I tried rolling back to 1.8, re-upgrading to 2.0...nothing seemed to fix it. I ran the front panel test mode (where you hit all the buttons and turn all the knobs) and it passed. Could have been stuck in a weird firmware state? I dunno, I was stumped. I debated contacting support but I bought from Sweetwater and figured it would be a good test of if it was worth paying full retail for their customer service. Turns out it was, they were awesome and had a new one to me before I could even box up the old one.