MP2 Instant Volume Increase

[Dante]

I did that too, but it only worked temporarily. I cleaned the jacks with de-oxit (then inserting/pulling out a cord 1,000 times)

[Kim]

I changed the patch cable ( which I bought new) with my another old one and as yet, I hear no problem.....

I did that too, but it only worked temporarily. I cleaned the jacks with de-oxit (then inserting/pulling out a cord 1,000 times)

My #1 MP-2 started doing this about 2 months ago, seemingly at random.  I cleaned the jacks and switches as best I could and hoped for the best.  However, it still happened randomly so I bought another MP-2 for backup.  Wouldn't you know, the #2 unit did the same thing.    :(
Now, I'm experimenting by actually using BOTH MP-2s in my Live Rig.  #1 is used as a preamp/compressor for the EHX "9" pedal section of my rig, and #2 is my guitar preamp.  #1 has nothing in its Loops, and is currently working flawlessly there.  #2 continued to do the Volume Increase at random, and it is using the Loops.  The last time it happened, I reached back there and wiggled stuff around while it was acting up and appeared that one of the patch cables was causing it.  I pulled that particular pair of cables (shit Radio Shack ones) out and replaced them with new cables of a better quality.  Since then, it has only happened once so far and just a little wiggle of the cable inside the jack fixed it.   

I have concluded that the problem must be within the jack itself, and not the cables or switch.

[Dante]

I have concluded that the problem must be within the jack itself, and not the cables or switch.

I have to agree. I came to the same conclusion with mine, but I just stopped using it. It embarrassed me at a gig and that was it  :nono:

[MarshallJMP]

What happends if you set the loop to off?

[Kim]

What happends if you set the loop to off?

I haven't tried that, but I will remember to check that whenever the problem comes back again.   

[Hanneman213]

Update; I was very happy to solve this one, yesterday I was having fun with my new Mooer Radar with various Impulse responses through headphone, but it repeated. Tried 3 different cables, all 4 outputs (including recording outputs). It was random. I was doing it though my TC Gmajor 2, ( when I play with headphones Tc began to be noisy  :facepalm:)
I activated noise gate of tc. Later I plugged MP2 Only. The Noise gone, gain turned back and first I thought the problem was on G Major2. But The problem repeated again  I was about to burn and throw it from the window. Left them simply, without gathering anything, went to bed.

[Hanneman213]

I turned to out in stereo fx loop, I will try in this way.

[Hanneman213]

Day Two: No problem yet. Besides, I dont use FX loop, I connect serial. So I shut down completely.