Hi domarius,
I'm going to chime in here with my own opinion that you're on the right track. Yes, it is perfectly possible for one speaker to have issues but not the other; that knob you're turning is actually controlling not one but two potentiometers, one for each channel.
That's definitely the next step, to open it up and spray down that pot with your contact cleaner. Spray it, look for holes to get it inside and turn the knob to help distribute the cleaner and scrape off the contamination. There's a fair chance that's all it needs, but if that doesn't do it you'll probably end up needing to replace it. Take pictures while you have it open so you can hopefully identify a replacement part should it be necessary. You'll want to take note of the resistance range of the potentiometers, along with the number of contacts on each pot as well as the number of pots if it's other than two. You'll need to know if the switch has an "off" position or not; you know, like a car radio where you turn it all the way down till it clicks to turn it off. Most home stereos don't, but you need to know that.
Give it a good clean then come back and let us know how it goes! If that doesn't do it, we'll try and figure out what your next step should be.