more sound in left channel than right channel?

I have a tube integrated amp equipped with four kt88 tubes. for some reason im getting a lot more noise coming from the left side than the right. it throws off the whole balance of sound. Is this a sign of bad tubes or need bias? New to tube amps and at a loss. thank you-
Flip the left and right channel tubes and see if the noise travels with the tubes...If so you need new tubes..If not its something else othere than tubes.......
I would swap the left and right RCA coming into the amp first. If the sound is still louder on the right than it's not your source. Checking bias is always a good thing and if you haven't done it I would.
If that doesn't do it try signal tubes first as you don't have to wait as long for them to cool down. If that makes no difference you could swap the two left KT88's into the right position and the right tubes to the left position. If you do this you must re-bias the amp.

Good luck

Please don't take this wrong but at my age (58) my hearing has diminished some to where my right ear hears about 75% what the left ear hears. I use the volume/balance control to compensate for my slight hearing loss in my left ear. If this isn't the problem then you are the lucky one.