Channel imbalance with turntable playback

You need a Test Record to check channel orientations, phase and polarity. Look for Cardas Test LP or Hi-Hi News Test LP.
There is only one right position for all cables in your system from cartridge lead wires to your speaker cables. You have to check all of them using a test record!

No!

"...There is only one right position for all cables in your system..."

No you can swap two sets of cables and get back to normal stereo. You can swap phono pre and pre or pre and amp, etc. 

You can swap whatever you want, but if you’re listening to a stereo source then your Left speaker is L channel and your right speaker is R channel, just like on the master. There is a simple test on any test record, the voice recorded on LP will tell you which channel it is originally, and if the voice appeared from the wrong channel then you must swap cables L R channels.

There is also phase and out of phase test, in polarity and out of polarity test.

Those TEST records are made for system adjustment.

If you want to know what's right and wrong USE A TEST RECORD!

@chakster even if I do find phase or polarity problems, how would I go about adjusting those?