Film-Tech Forum ARCHIVE: Lost the center sound channel (and got it back)

This is topic Lost the center sound channel (and got it back) in forum Digital Cinema Forum at Film-Tech Forum ARCHIVE.

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Posted by Frank Cox (Member # 6258) on 09-27-2016, 09:34 PM:

This is something I've never seen before.

I started tonight's movie and the center sound channel was missing. Everything else was working fine. No center sound in the auditorium or on the booth monitor.

I powered down the GDC server and the sound rack (JSD 100 sound processor), then booted everything up and started the show again and it worked perfectly.

Posted by Harold Hallikainen (Member # 5405) on 09-27-2016, 11:21 PM:

I hope that did not disrupt your show too much! It would be nice to know which piece of equipment had the problem, but I suspect there was not much time to experiment.

Harold

Posted by Frank Cox (Member # 6258) on 09-28-2016, 12:09 AM:

In hindsight, I could have power cycled the JSD 100 first to see if the sound came back; it boots up a lot faster than the server does. Never thought of it at the time, though. My idea at the time was that one or the other of those two gadgets were at fault and I'll just reboot them both and hope it clears itself up. Which it did.

My show ended up being about ten minutes late starting, but there was nobody here that was under about 70 years old tonight and they were actually singing songs while they were waiting for me to get it going. So I guess they kept themselves entertained. [Smile]

Posted by Mike Blakesley (Member # 26) on 09-28-2016, 01:37 AM:

I had a similar thing happen a couple of weeks ago -- started the movie like normal, everything looked and acted normally but we had NO sound at all. I first was suspecting the Dolby CP650, so I rebooted that, since it only takes a minute...still nothing. Rebooted the projector and SX3000, and it worked fine and has worked fine since. We didn't have a late start because I discovered the problem during our ad package, so I was able to leave off the last half of the package (which is just a repeat of the first half) and start the main program.

I hate those kind of problems where you don't know WHAT the hell happened, or why.

Posted by Steve Guttag (Member # 268) on 09-28-2016, 08:08 AM:

Channel oddities on GDC servers is not an unheard of thing. What firmware are you running?

Posted by Mark Gulbrandsen (Member # 72) on 09-28-2016, 09:55 AM:

Yes, fairly common anomaly on GDC and it has something to do with the built in audio routing. 7.8 never did this, ever since 8.xx arrived they do this every once in a blue moon. So before starting your show up you might want to go out and check the moon first.

Mark

Posted by Martin McCaffery (Member # 37) on 09-28-2016, 11:15 AM:

Fortunately, there isn't a Blue Moon until May 18, 2019.

Posted by Mark Gulbrandsen (Member # 72) on 09-28-2016, 11:47 AM:

Ok... then I will plan on getting at least one call from a customer that day asking why he is getting the hearing impaired track in his left screen speaker. That seems to be the most common mode it goes into when it does it. A quick reboot always fixes it.

Mark

Posted by Frank Cox (Member # 6258) on 09-28-2016, 10:26 PM:

quote: Steve Guttag
What firmware are you running?

8.01 build 244

Posted by Stephan Shelley (Member # 8587) on 10-12-2016, 07:17 PM:

Had a service call on a GDC running 8.01 build 258 and found no L,C,R but left surround was coming out of left front and right surround out of right front.A reboot of the server and IMB corrected the situation.Sent GDC a copy of the logs and they are looking into it or so they say.

Posted by Mark Gulbrandsen (Member # 72) on 10-12-2016, 08:52 PM:

LOL... They have been looking into it since 8.01 Build 108! The SX-3000 will also do it when the moon is blue and the wearwolves are out. Not sure about the AR series servers. I only have two of those in the field.

My customers know to reboot if this happens.

Mark

Posted by Jason Raftery (Member # 6291) on 10-12-2016, 09:44 PM:

It happens on the ARs from time to time (at least through software version 9.0-build389), too. Typically the first show after a server/projector power cycle is where I've encountered it. Power cycling only the projector (IMB) and leaving the server running always resolves the problem--although in one memorable case, the audio misrouting reoccurred and required a 2nd IMB reset. GDC has claimed they've never been able to duplicate the issue and that the malfunction leaves no trace in the logs. [Confused]