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ncpl
2006-10-16, 12:30
Twice now, from a cold boot up of P.C. and SS and with SB3 coming out of std by with a status of nothing playing, I play a track (any track) and get only one channel. On the first occasion it was right channel; next time it was left.

The only way to restore the missing channel was to unplug power and reboot the SB3.

The SB3 directly feeds Meridian digital speakers which work with a full digital signal to one speaker and then linked to the next. L or R speaker designation determines which half of the signal to play. The speakers don't indicate any signal locking issue and as it's happened to both channels and is fixed by a SB3 reboot, I suspect the missing channel is missing from the SB3 output.

Anyone shed any light on this ?

cheers

seanadams
2006-10-16, 13:01
Twice now, from a cold boot up of P.C. and SS and with SB3 coming out of std by with a status of nothing playing, I play a track (any track) and get only one channel. On the first occasion it was right channel; next time it was left.

The only way to restore the missing channel was to unplug power and reboot the SB3.

The SB3 directly feeds Meridian digital speakers which work with a full digital signal to one speaker and then linked to the next. L or R speaker designation determines which half of the signal to play. The speakers don't indicate any signal locking issue and as it's happened to both channels and is fixed by a SB3 reboot, I suspect the missing channel is missing from the SB3 output.

Anyone shed any light on this ?

cheers

That's a new one. It's very hard for me to imagine anything that could go wrong in the Squeezebox which would cause one channel or the other to go out like that. S/PDIF, particularly the way SB3 generates the signal, is just not really subject to that kind of problem - you either have the data or you dont, and there's nothing special that makes one channel different from the other.

Some ideas which might shed some light on this:

- Try a different source component to verify that the problem isn't in the speakers

- Try SB3 with a different receiver

- Next time it happens, instead of rebooting the SB3, try unplugging and re-plugging the s/pdif cable.

- Try a different cable, or different type of cable (eg optical instaead of coax).

- Next time it happens, try playing something at a different sample rate (48KHz or 32KHz material) and see if it starts working again. This causes the interface to have to re-sync.

- Try toggling the l/r setting on the Meridians

ncpl
2006-10-16, 13:29
Hi Sean,

Thanks for the quick response. I can comment on a couple of your suggestions which may help narrow it down:-

- Try a different source component to verify that the problem isn't in the speakers---- I can switch between sources and all other sources seem fine.

- Try SB3 with a different receiver----I was previously running the SB3 into my processor and then into the speakers. I can still do this if I switch cables to the SB3 as I'm using both digital inputs to the speakers. I am currently trying the SB direct to the speakers to see how they go as the speakers will upsample internally etc.

- Next time it happens, instead of rebooting the SB3, try unplugging and re-plugging the s/pdif cable.----I'll try that. I'm not doubting the cable as such (although wouldn't rule it out) but suspect this might give the speakers another chance to lock. It is very odd though that it has done it both sides now. I agree that spdif is normally both channels. The Meridians work with one speaker as master which gets the spdif feed first and then passes the full signal to the other slave speaker. I haven't seen it on any other source or when the SB3 was into my processor.

- Try a different cable, or different type of cable (eg optical instaead of coax)---- I can't do that to the speakers as they only have spdif inputs. I can do that into the processor though. I'll try that after trying the spdif back to the processor when it next happens.

- Next time it happens, try playing something at a different sample rate (48KHz or 32KHz material) and see if it starts working again. This causes the interface to have to re-sync----I only have 44.1k flacs at the moment. I'll have a look at some 48k PCM material I have on DVD. Would going to standby and with both speakers and SB3 also not cause it to re-sync ?

- Try toggling the l/r setting on the Meridians---- that's worth a thought. However, I'll have to switch the DSP's off to do that so that might be the same as unplugging the cable.

I guess I'll have to buy a Transporter so I can feed both direct to speaker and via the processor simultaneously eh ;).

It's only happened twice in about a week so it may be a few days before I catch it again.

I'll post back when I do.

All the best

ncpl
2006-11-12, 12:10
Hi Sean,


I said I'd post back....

It's just done it again today for the first time in ages. I unplugged and replugged the spdif cable on the SB3 and it resolved the channel issue. I suspect therefore it may be an issue with how the DSP's are handling the feed from time to time.

cheers