Logitech Z-5300: Amplifier has a bad satellite output

[spongebue]

Hi all,

I've got this Logitech Z-5300 (technically 5300e, but that's just a different color from what I can tell) speaker set that I picked up at a thrift store for $30 yesterday. Everything seems pretty nice, except for one glaring issue: the left front satellite output seems to be bad. I did try switching speakers, and it's always whatever's plugged into that one plug that doesn't work. I opened the amp, and from what I can tell there doesn't seem to be anything obviously with it on the currently exposed side.

I'd take out the whole board now, but that seems like it'd be a little easier said than done: the nuts holding the board in place almost seem to be glued to its bolt or something, since I'm having a hard time keeping it from spinning around when I unscrew it (in all fairness, I've only tried holding it in place a crescent wrench or pliers, since it's pretty small and I don't think I have anything small enough for this).

I'll look at this more after work tomorrow, but in the meantime I thought I'd post this to see if anyone has any thoughts or suggestions on what to look for, what kind of work I have cut out for me, etc. I'm hoping it's a bad fuse, but who knows. It does help that I can (theoretically) swap components from another channel if I suspect that a certain part is causing the problem, I figure.

Any comments would be very much appreciated!

Thanks,
Brian

[spongebue]

Ok, little update that might help for troubleshooting:

First off, the satellite is not totally dead, but it's very silent. When I adjust the volume with the wired remote, it does get louder or quieter (of course, even at the loudest setting the speaker has to be right up to your ear to be able to hear it).

The next possible piece of the puzzle is that this is the only speaker that makes a small "pop" noise for each click the volume is adjusted, which has different volumes depending on what's current for that.

I've gained access to the motherboard on both sides, and figured out which section is for the channel in question. With luck, it'll just be a bad capacitor. Otherwise, it might just be that chip, which doesn't have any label and might be proprietary

[jaycee]

If you're lucky it's a cracked solder joint at the connector. does wiggling it help?

It's unlikely to be a blown fuse - odds on all the power amps are protected by one set of fuses, so you'd lose the lot if a fuse popped.

[spongebue]

upon closer look, it definitely seems like it's the input that's bad. I noticed that both front left (the yellow one I mentioned earlier) and front right are duds when I have it on 2 -> 5.1 mode. If I flip the switch to 5.1->5.1 (so each channel has its own input) the left rear one will come in from a different input, and that comes in beautifully like that. Front left is still bad, but it's supposed to come in on that same jack anyway. I'll update shortly.

[ceteras]

I know this thread is dead for a long time, but I have a broken Z5300 here too.
It has exactly the same issue: front left is dead, rear left "dies" too if I switch to 2->5.1.
Also the clicks are there when I move the knob, but only when I adjust the volume, not so for the knob's other functions.
I remember I've fixed a Genius 5.1 system a while ago, with similar behaviour, and the solution was to replace the volume controller IC.
So I think in our case it's the same issue, in z5300 this is NJW11500.
It's datasheet can be found on Internet, but I can't find a supplier.

I think others could use this info, so I've decided to post here.

[ceteras]

I apologise, the IC is NJW1150, actually.