It is not normal. Most singers are center stage. Sit in the central listening position and play a complex piece like a symphony orchestra or a NIN tune. Close your eyes. There should be an equal amount of energy coming from both sides. If one side is always heavy handed then you do have a balance issue. It can and most likely is a room issue especially if it does so with all sources. Use your balance control to center the energy. If your problem is frequency related such, as an example your high frequencies are skewered to one side then you need a room control preamp or an expert at room treatment which will require measuring the room. Other things can go wrong. A bad speaker or cartridge can do this.
Having said all this, recordings can vary and I find the very best systems in well designed rooms require a little tweaking from one to another. We are talking around 0.5 dB. Most systems in the rooms they are in do not have this kind of resolution. There is too much noise coming from reflections.