Ok to adjust balance to achieve center vocal image?


I have an all analog tube vinyl system and don’t remember having to adjust my balance setting in order to achieve a center vocal image. I do now though. I’m getting a left leaning vocal image with the balance set to zero. Is there a good way to see if this can be fixed so I don’t need to balance adjust to achieve a center vocal image? Could it be a preamp tube going out? Something else? Any harm in just continuing to adjust the balance - meaning am I experiencing any signal loss doing so? 
Thanks! Paul
paulgardner
Clearaudio Satisfy or Verify?? Makes me think of a tonearm run without enough anti-skating or a turntable that’s altered its levelness.

Exactly yogiboy!
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I have the same problem. Have a Rogue Metis preamp. It’s different album to album but always right side is stronger than the left. I just use the balance to compensate tried find the problem but gave up. Just use the control and enjoy the music.
Also, some older jazz vocals were actually originally recorded in mono and then later electronically converted to produce a stereo LP.  In the process, some engineers seem to have placed the vocalist mostly on one channel, typically the left in my experience, and then they placed the rhythm section, at least the bass and drums, on the right.  It's folly to try to fix that particular situation with a balance control.  Best to live with it.
Tone arm is the stock magnetic bearing one. I’ll check the setup there. 

Hmmmm. I probably just stick to adjusting the balance control if its not an easy fix like a couple have suggested.

Thanks guys!