DJM-S7 fader issues

After about a month I noticed my channel 1 fader acting weird when i open it all the way. It was dropping the sound almost like when a fader is bleeding. So I figured dirty fader, I'll just use it in reverse until i can open and clean, but it does it in reverse too!  Now my channel 2 is starting to do the same thing and it's pretty annoying.  the other not so great thing is the channel faders used in the S7 are pretty shitty and soldered to the main board, so if you do want to try and service them you have to dismantle the whole mixer.  Anyone else having this issue?  Is it going to be faders or the board??