2 speakers in 5.1 system not working

[bluhorizons]

Looking for some info and advice on a problem.

I upgraded my HT system after buying a blu ray player. I gave my old unit (an older Sony HTiB) to my parents as they have never had a home audio system of any kind and they don't like to spend money on things like that.

Anyhow, they very much enjoyed the system for several months but when I went to their home the other day they told me about a problem that I looked at but was not able to resolve.

They said the sound coming from both the right front and left surround (rear) speakers were very, very low. I first did a tone test and this was the case. When the test tone came to those speakers the sound was very, very low but there was a faint sound produced.

Doing a test tone they were correct and the R front and L rear speakers were barely putting out any sound. I did a bunch of tests and speaker checks and checked wires all of those were fine.

What I did discover is that when I connected both of the non-working speakers into a different speaker output terminal, they worked fine. And when I put a working speaker into the terminals of the speakers that were not working, the working speakers then did the same thing-only playing at a very, very low lever.

So this pretty much makes the problem with the receiver as working speakers didn't work in the non-working terminals and the suspect speakers worked in other terminals. So the R front and L rear terminals only play at very low levels and there is no adjustment that can be made in the receiver that would affect individual speakers (just left/right, front/back settings exist).

So I would like to hear what the problem might be and what kind of fix (if any) could be made as I don't expect them to purchase another system. All assistance would be appreciated.

Thanks,
DB