Reply to Bit of a mixer problem... Audio Innovate AEM100i

Basically I've had this mixer (the Innofader version) for over three years and in the last half a year or so it seems to be giving me a bit of trouble. Not helpful when I live in the UK and this mixer is only in the US really. The line faders are a little crackly, but that's not the main problem. The EQ sliders and volume knob on the left channel (deck 1 etc) seems to be really crackly and if I move the volume knob or EQs, the channel decides to only give me audio in the left or right ear. If I move them a bit, it will go back to normal but as soon as I tweak the volume or EQ, most of the time i have to move it again as the same thing happens over and over again. I have put switch cleaning lubricant etc and even opened the front panel to dust it, but my hopes of one day selling it on seem to be fading I have used it every day and there's nothing wrong with the Innofader luckily.

Any help?