Cheap Surround sound buffer/level shifter

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JR.
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Re: Cheap Surround sound buffer/level shifter

Post by JR. » Tue Dec 15, 2020 1:35 pm

Well the low level hum buzz is fixed but I just noticed that the surround channels were quiet...

Hard to trouble shoot with multiple moving parts in the path that could cause the issues.

I wired up an old stand alone stereo amp to some separate speakers and tried substitution.

#1 I discovered that there was no surround data coming from the optical feed from the TV monitor. The optical feed from the direct TV receiver has the surround info. This was working before so the roku enabled TV (cheap walmart house brand got stupid). It is getting HDMI feed from direct TV and auto detect only reads stereo not dolby surround. It was working just a couple weeks ago.

#2 even with the optical input changed the rear channels are still quiet so I need to debug wiring from decoder, through bump box, to hypex amps...

This is turning into a high maintenance girlfriend....

JR
Cancel the "cancel culture", do not support mob hatred.

User avatar
JR.
Posts: 3600
Joined: Sat May 24, 2008 7:21 pm
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Re: Cheap Surround sound buffer/level shifter

Post by JR. » Thu Dec 17, 2020 2:00 pm

I really hate troubleshooting issues that are occurring between two different systems. I also hate troubleshooting problems that just randomly begin with no obvious cause.

I am suspicious of modern smart appliance protocols where devices can communicate back and forth. I am pretty sure that my Direct TV HDMI output is not enabled for bidirectional control communication, but the Roku enabled TV monitor apparently is.

The Direct TV receiver setup menu only has one dolby on/off setting and that has been on. The roku monitor has about a half dozen different dolby variants (none of them work). The auto detect mode says it is detecting " stereo" and that is what is coming out.

So optical output from direct TV receiver has 5.1 dolby surround, optical output from roku TV is stereo only. The HDMI feed between direct TV and roku clearly had surround audio in it before but not now. I suspect the Roku is what changed.

I am tempted to do a hard reset on the Roku to return to factory initial conditions but I may not have the secret handshake codes handy for repeating initial set up.

JR
Cancel the "cancel culture", do not support mob hatred.

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