Logitech Z-5500 Amp Troubleshooting

[TooManyUsers]

Hello to all.

Does anyone here have any knowledge of the amplifier section of the Logitech Z-5500 system (that is about as simply as I can put it)?

I have read through the entire "Hacking the Z-5500" thread a few times now and most of the focus there is surrounding the common faulty control POD issue and therefore solutions to eliminate the need for the POD.

I have what also seems to be a common fault as well (many similar unanswered questions), but cannot find any troubleshooting pointers anywhere online so far, hence trying this post here.

My Sub is dead, but the driver itself is fine (taken out and tested on external amp) as is the control POD and all satellite/centre speakers and their amps.
All wires trace (continuity) between the POD and the PCB inside the Sub and that is as far as my knowledge goes I am afraid.

Anyone know how I can "test" the op-amps or transistors or whatever other component/s in these Z-5500's is likely to go?
Would also be useful if someone knows which ones are dedicated to the subwoofer and what simple tests I can carry out to make sure that the amplifier section is at fault and NOT perhaps some other more complex issue?

Thanks for any help.

Steve