iPod Classic: Erratic lock switch - before & after replacement

iPod Classic 160G

Initial problems:

Lock / hold switch worked intermittently - in the unlocked position the lock icon blinked on & off. If you could select functions in between blinking the iPod worked fine.

Would not hold charge - charge icon would rarely come on but it would indicate a full battery after several hours of charging.

Repair:

Replaced battery and lock switch / earphone jack

Restored via iTunes - multiple times

Reformatted drive in disk utility - multiple times

It will accept playlist and function normally when it's not freaking out which is 98% of the time ...

New & continuing problems

Lock switch still intermittent- blinking icon

Won't stay asleep (press and hold pause) wakes up 30 sec. later

Won't wake up unless plugged in then you realize lock icon is on or blinking rapidly .... lock switch position is irrelevant.

Pretty lost .... is my new switch defective or am I looking at a logic board or hard drive issue?

Any suggestions welcome

Phil

Thanks Tony,

Sounds like a good fix, I'm assuming Apple won't do this so I'd have to find a independent electronics guy. Is the diode easy to locate? I'm down here in the tropics and not to confident about local diagnostic skills. Not to mention the boards pretty small! Any pointers would be really appreciated.

Crash