Azimuth will not affect channel balance, it will affect tracking and record wear but not balance. Nor will VTA, but never hurts to double check cart alignment especailly if you haven’t in a while for overall sonics. I would check all cable connections including your cartridge pins and obviously tubes.
But do not be afraid to use your balance control, and adjust speaker toe in and distance from the front wall where the balance is off. Annoying I know!
But do not be afraid to use your balance control, and adjust speaker toe in and distance from the front wall where the balance is off. Annoying I know!