Hello, I’m Nathan, and I’ll be assisting you today. My livelihood depends on your positive feedback, so your satisfaction is my highest priority.
Sorry to hear you’re having trouble.
This type of problem is often caused by a worn or contaminated laser lens. You can attempt to clean it by blowing out the disc tray/slot area with a can of compressed air for dusting computers (keep the can upright only so you don't get chemical propellant on the lens).
If this doesn't help, you can try a specialty cleaning disc (Allsop 23321 Ultra Pro Carbon-Edge DVD and CD-Drive Cleaner) which has little brushes that clean the lens more thoroughly.
If neither of these cleaning steps help, then this is more likely a hardware fault, which could include a bad laser emitter or pickup, faulty spindle motor or laser transport, bad d/a converter, etc. Any of these issues would require repair/replacement.
While it is possible to fix, you are correct that you may end up with different components, as original technics parts for this unit won't be available any longer. The cost would be a factor as well. Replacing the optical assembly could quickly end up costing you more in parts and labor than you would spend to buy a whole new player (current model, fresh warranty, etc). Of course it wouldn't be an exact match aesthetically, but may be something to consider. If needed, I'll be happy to help with finding parts, finding a repair shop, or recommending replacement options.
This problem seems to be a soft wear issue as the second unit locked up when using the track program function, until then it had worked fine. Do you think there is a way of doing a hard reset on the unit. Its almost like I have asked it to find track 4 and not start at track 1, and it cannot find track 4, but I'm unable to cancel the request, consequently it will not play any CD