If the clean doesn't work, you can open it up and re-solder all the points on the PCB board.
Do search for AFM+ Solder+. GTST did a post on how to re-solder the AFM.
If that doesn't work buy a known working second handy as stolen_s15 said.
These suggestions we're giving you is the cheapest way of fixing your problem, Its going to cost a few dollars (literally $10ish max) if you can repair it yourself.
Going for a Z32 is going to cost at least in the $500 region after you pay for a tune.
IMO, jump the AFM hurdle when you get to it. When you hit your 210rwkw and the stock one maxes out, then get the Z32.
Happy AFMing