weird digital distortion????

    So I've got my Kemper wired into my board using both the main analog outputs and the S/PDIF for recording and reamping. I leave the system on all day and shut it down late at night. Lately, the system randomly makes a very weird digital distortion... like mega overdrive digital clipping. Initially, I reset everything, computer, board and Kemper to remove the noise but quickly got the Kemper isolated and now whenever it occurs, all I do is reset the Kemper, turn it off and then back on..


    The Kemper works perfectly most of the time, it's just this random digital breakdown. Today it happened while I was reamping and switching between patches. It reminds me of something like the digital sync gets out of whack and drops, then mega clipping...


    Does anyone have any experience with this symptom?? Any suggestions??

    Gettin' funky up in here..

    It can happen with any profile..... I just worked a sound Till's recto and after I tweaked the sound, I played it with the recorded lead through the S/PDIF reamping process.. it was working fine and then I noticed it.


    Never done a complete reset and restore. I just turn it off and back on, always works. (2.2.0.8917B version) Didn't notice it on previous versions.. I could restore a previous version and see if it occurs.


    I think next time, after the distortion occurs, I'll reroute the reamping through my mains and see if the distortion is there.. could tell me definitively if it's the s/pdifs or something else.

    Gettin' funky up in here..

    Check that a setting hasn't changed for your soundcard, specifically with regards the spdif clocking (kpa has ot be master, 44.1 etc you know the drill).


    Alternatively check your ground lifts and for anythign else plugged in to the kemper from aux inputs.


    There's also the possiblity that you're accidentally turning off the cab, either from the master section or on the face of the unit, there still seems to be some flakeyness with the Kemper and MIDI messages doing weird things.


    Apart from that, yeah do a reset, and if all else fails start checking your cables for a ground/sheilding issue. Oh and of course if your guitar has active pups don't forget to change that battery (yeah I know I might be insulting your intelligence, but everyone I know that has active pups has been caught out by this sooner or later because of the length of time between battery changes it's so easy to forget what happens).


    If all else fails then time to call Kemper Tech Support, they're pretty responsive.


    Good luck!

    Well, I believe that I verified that it only occurs on the spdif connection. When it occurred today, I solo'd the analogs and they were clean' solo'd the digi's and bad distortion. I reset the KP by turning it off, then on and the digi's were fine. So there is a failure in the spdif's.. now is it in the inputs or outputs?? dunno just yet.


    The problem is that I cannot "make" the fault occur; I have to wait for it t just happen. so with that, I can't isolate the "why" as what's happening to make it occur. I know that today, I was messing with the spdif volume, turning it up to zero db and then backing off; back and forth. I was trying to determine if the spdif was introducing a slight distortion/digital edge to the guitar sound that was dofferent fro the analogs... (I couldn't determine a difference in sound) This was brought on because I think I'm hearing the "stack" side of the spdif being reamp'd instead of the "guitar" clean side. This makes for increased distortion and a change in sound from the original... of course... this is what I think that I am hearing and am trying to figure out why...

    Gettin' funky up in here..

    Quote from DukeOURL

    Well, I believe that I verified that it only occurs on the spdif connection. When it occurred today, I solo'd the analogs and they were clean' solo'd the digi's and bad distortion. I reset the KP by turning it off, then on and the digi's were fine. So there is a failure in the spdif's.. now is it in the inputs or outputs?? dunno just yet.


    The problem is that I cannot "make" the fault occur; I have to wait for it t just happen. so with that, I can't isolate the "why" as what's happening to make it occur. I know that today, I was messing with the spdif volume, turning it up to zero db and then backing off; back and forth. I was trying to determine if the spdif was introducing a slight distortion/digital edge to the guitar sound that was dofferent fro the analogs... (I couldn't determine a difference in sound) This was brought on because I think I'm hearing the "stack" side of the spdif being reamp'd instead of the "guitar" clean side. This makes for increased distortion and a change in sound from the original... of course... this is what I think that I am hearing and am trying to figure out why...


    That sounds like your DAW or soundcard is changing the left channel of the SPDIF to the right and vice versa. Do you have any other SPDIF equipment that you could use to verify this? Are you using some sort of converter to change the coaxial SPDIF to an optical format?

    @DonPeterson, I'm using a Yamaha 01V96i for the AD/DA conversions into a Macbook Retina running current IOS.


    deadpan, yep, I agree that this can cause unwanted, unnatural distortion but is not the cause here. Mine is infrequent.


    Lambik, I can change left and right side assignments for my SPDIF's easily with the board I/O and Cubase. I've got this issue under control now. I was actually hearing the stack side being reamp'd which just wasn't natural sounding. I also have the ability to change the volume of the S/PDIF real time, which was contributing to the unnatural sound. I backed off on the track volume routing back into the Kemper during reamping which helps clean things up.


    My issue is still something happening to the Kemper S/PDIF's causing a digital distortion infrequently. Resetting the unit fixes it; I am yet to determine what is the root cause of the failure.

    Gettin' funky up in here..