So, about a year ago I did a little parts caster tele build and wired it up with a 4-way switch to add the parallel pickups option. It worked great for a few months and I loved it, but one day I noticed the volume knob began acting more like a tone knob. When it is rolled down it brings the volume down a hair and mostly rolls off the treble. I finally got around to working on it some more today and I redid the grounds to the volume pot because I read that was a common issue and it worked like normal for a few minutes then went back to the old issue. Any ideas on what could be the issue? Thanks!