Little Mark Tube 800 Volume Issue

Discussion in 'Amps and Cabs [BG]' started by bassindood, Jan 30, 2020.

  1. I’ve had my Markbass Little Mark Tube 800 for almost 4 years now and I’ve run into this issues for the second time. Whenever the “mix” solid state/tube dial is set to 100% tube the volume gradually cuts out almost entirely after a few minutes of playing. The volume increases back to normal when the dial is turned back to solid state.

    2 years ago I sent it out for warranty repair to have the issue fixed. They replaced the pot, which seemed to do the trick. The issue came back about a month ago. I brought it to a local tech who told me the soldering job was done sloppily and he cleaned it up, but that did not solve the problem. I assume the tube is ok, considering neither tech thought it was bad. What could be causing this problem?

    Little Mark Tube 800 played through a Markbass New York 151.

  2. *UPDATE*
    I had a tech attempt a fix and it seemed like it did the trick, until now. He thought some paths near the pot were getting crossed on the board, so he did some re-soldering and it seemed to be fine. Now I'm getting the same issue. However, after some poking around I have now discovered that when the sound is out and the dial is turned all the way to the tube side, if I toggle the Phantom Power switch next to it on and off, it seems to fix the problem momentarily. Any thoughts?
  3. agedhorse

    agedhorse Supporting Member Commercial User

    Feb 12, 2006
    Davis, CA (USA)
    Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
    Time for a tech to do a more thorough troubleshooting, THEN repair what's actually wrong. To this point all that's been done is guessing.