Right Channel louder than the left


Hi
I have a Nottingham Ace Spacedeck and the Ace Space Tonearm fitted with a Shelter 5000 cartridge (MC). I find that the right channel is slightly louder (more dominant) than the left channel (this is also reflected in the VU meters of the pre-amp Mcintosh C2200). I was wondering what my options are to correct this interms of adjustments. Would changing the anti-skate work or should I be looking at an azimuth adjustment (help needed on this one) or something else.
Also what equipment would I need to do this.

thanks in advance
dravid1
I just switched the wires on the cartridge and the levels are OK. I switched them back and it looks like problem has gone away or is barely perceptible. Maybe a faulty connection that got resolved?
thanks for the help
Newbee you are right the AUX in (to which my phone stage is connected) does have its own tubes. The weird thing is that the problem has now gone away when I flipped the connections back and forth on the cartridge.