Can you replace the cinch cable from your turntable to the mixer? Unbalanced input means to me that there is something wrong with the signal from the tts to the mixer. I am not sure if you can replace them, at my technics I could not :-(
Maybe it is the needle! Be sure that it is working well! Screw it off the tonearm, blow away the dust or dirt that may be on it and screw it back. Also be aware that the needle is connected correctly to the system.
My thoughts so far

Greetings,
Steve