I recently added a Sonos Amp to my system, replacing an old traditional amplifier. I want to send the audio from my 8-year-old LG HD TV (model: 42LE5300) to the Amp but my otherwise perfectly-functioning TV only has an optical digital audio/TOSLINK output - and Sonos chose to only offer an HDMI input (and RCA component audio input) on the Amp.
The NYC Sonos store was nice enough to give me a dongle (which apparently came standard with the Beam but is otherwise not available) to connect the optical digital output to the Amp via HDMI. However during setup the Amp says it does not detect an audio signal from the TV. To troubleshoot I tried connecting the dongle to the optical digital audio output of my very new cable box (a Cisco Technicolor 4742HDC2) - and the Amp still says it doe not detect any audio signal.
I've read through the manuals of both the TV and the cable box to make sure that there wasn't anything I needed to do to activate the optical digital outputs (as far as I can tell, there wasn't on either of them). Since I've swapped everything else, I can only assume that the dongle doesn't work - but the otherwise-helpful NYC Sonos store says they don't have another one nor will they let me test it on their in-store setups.
Any ideas where to turn next?
Connecting a Sonos Amp to LG TV via digital optical output & HDMI dongle
This topic has been closed for further comments. You can use the search bar to find a similar topic, or create a new one by clicking Create Topic at the top of the page.
First off, where'd you get the idea that the optical to HDMI-ARC was otherwise unavailable? While it's included with the Beam, it is also for sale here:
https://www.sonos.com/en-us/shop/optical-audio-adapter.html
If I were to hazard a guess, your Cisco cable box is putting out something other than Dolby Digital. So, that signal (DTS, maybe?) is being passed to your TV, and then passed through the TV to the Sonos Amp, which can't read it.
Take a look at the audio settings on both the cable box, and then the TV, and make sure that they're both locked down to Dolby Digital. Note, especially on the TV (no idea about the cable box) that you must be watching a stream that has a Dolby Digital signal to make the changes, otherwise they may be greyed out.
https://www.sonos.com/en-us/shop/optical-audio-adapter.html
If I were to hazard a guess, your Cisco cable box is putting out something other than Dolby Digital. So, that signal (DTS, maybe?) is being passed to your TV, and then passed through the TV to the Sonos Amp, which can't read it.
Take a look at the audio settings on both the cable box, and then the TV, and make sure that they're both locked down to Dolby Digital. Note, especially on the TV (no idea about the cable box) that you must be watching a stream that has a Dolby Digital signal to make the changes, otherwise they may be greyed out.
Hey, thanks for that. I had looked previously and hadn't found it, but there it is.
Take a look at the audio settings on both the cable box, and then the TV, and make sure that they're both locked down to Dolby Digital. Note, especially on the TV (no idea about the cable box) that you must be watching a stream that has a Dolby Digital signal to make the changes, otherwise they may be greyed out.
Thanks again! You inspired me to try something different - I switched the input to the TV from the cable box to the AppleTV and lo and behold, the audio was successfully passed through the Sonos! So apparently the root of the problem is the source audio from the cable box.
I have very little documentation for the cable box (Cisco Technicolor 4742HDC2). The only audio option I can get to via menus is preselected to "Digital" - there's no other option - and then you can select "Language 1" or" 2". I've googled until I'm numb and can't find any clues as to how to change the audio output format - I don't suppose you (or anyone else) has any idea if it's possible?
Hmmm. One other thing to consider, since you're willing to do some testing.... try swapping the two inputs, so the Apple TV HDMI cable goes in to where the cable box HDMI cable is right now. Not that I'm sure about anything, but it seems odd to me that one input works one way, and the other works another. The implication to me is that either the source type is different (i.e. one is doing stereo, the other Dolby Digital) or that the two HDMI ports are handling the stream differently.
Now, in my "I'm not there" opinion, it's more likely the former, rather than the latter, but swapping the inputs would prove that. Or looking at the settings on the output of the Apple TV. It just strikes me as odd that two different HDMI inputs would treat the incoming signal differently.
I've had the opinion that there are some TVs that delay processing on a Dolby Digital signal for some reason (including doing extra processing for 'bonus' features...you should always have all of those turned off in the TV's audio settings), but I've never run across a TV set that deals with the same signal in different ways on different inputs.
Unfortunately, I'm no help on that cable box. I'd be calling the cable company and asking them, since they've not provided appropriate documentation for you. I do wonder is if "Digital" is Dolby Digital, or DTS, very different standards. But the people who provided you the box should be able to dig up an engineer who can give you real answers.
Now, in my "I'm not there" opinion, it's more likely the former, rather than the latter, but swapping the inputs would prove that. Or looking at the settings on the output of the Apple TV. It just strikes me as odd that two different HDMI inputs would treat the incoming signal differently.
I've had the opinion that there are some TVs that delay processing on a Dolby Digital signal for some reason (including doing extra processing for 'bonus' features...you should always have all of those turned off in the TV's audio settings), but I've never run across a TV set that deals with the same signal in different ways on different inputs.
Unfortunately, I'm no help on that cable box. I'd be calling the cable company and asking them, since they've not provided appropriate documentation for you. I do wonder is if "Digital" is Dolby Digital, or DTS, very different standards. But the people who provided you the box should be able to dig up an engineer who can give you real answers.
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.