logitech z680 question

i have had these speakers for over 2 or 3 years now and they are excellent, but my left rear recently stopped working, and its not the speaker, and its not the cable, i fear the output on my amp is screwed up. I do not know what to do, i cant find any z680 subs on ebay, and was wondering if the new z 5500 sub would work with this system, or if the connector from the pod to sub was different? Or if i got the new z680 sub, if I would be able to somehow use both subs and just run the sattelites off of the good one, and use the second one with the messed up left rear output just for added bass?

Hmm I don't know, computer speakers are pretty hard to piece together and upgrade, and who knows what Logitech has changed in the new z5500 subs. I would recommend that you either just deal with one dead channel or buy a new system.