Sudden problem with turntable

Check the VTA - vertical tracking angle. I had a very similar, very frustrating experience recently, and taught myself to adjust the height of the base of the tonearm. I raised it up and then slowly lowered it down in increments until it hit the spot where the sound was clear and beautiful again.

No love for my suggestion that would have cost you nothing. Too late for it now. Good Luck!

It’s the same physical album I have listen to many times so unfortunately not the pressing. 

Do you have HiFi News test lp? That might offer some clues...cheers,
Spencer

Take the cartridge out and send it to Soundsmith....you'll get back smiles again.  Don't bother with anything else since this happened suddenly....not a setup or cleaning suggestion.