Balance control?

I’m running an analog exclusive rig and feel like I’ve been dealing with a channel imbalance for awhile now. I’ve tried trouble shooting this every single way I can think of. The cartridge is set up correctly, checked tubes, etc. My question is: am I obsessing over finding the root cause or should I just cave and use the balance control on my integrated? I feel like it would be ideal to find the cause and not use the balance control. Dose using the balance control introduce anything into the signal? Ugh.