Dialog + dos 2 +plc = no sound

[jacob]

Hello,
I have a setup with a dialog and two phantoms. The audio chain is optical to dialog and plc from there to the speakers. After upgrade to dos 2, this setup has no audio.
If I move the optical from dialog to one of the speakers, it works.
I need the dialog and plc though, since I have no room for new cables in the walls and I can’t have cables dangling outside on the wall to the wall mounted phantoms.
(I practically build the wall to the phantoms).

I did read a lot about dos 2 before the update, and as far as understood my setup should still work under dos 2.
Has any of you any experience with at similar setup, thus optical + plc + phantoms +dos 2?

Cheers,
Jacob

[quartz78]

hi @jacob
Yes, it absolutely should work.
- Do you see your Dialog in the app? It is in the Main settings > My products > Accessories
- In the volume control screen, choose "Aux" on the bottom, scroll right... is there "optical (dialog)" there? Try selecting it.
- What's your source? Is it plain PCM stereo? What bit depth/bit rate?

[jacob]

hi @quartz78
I am in contact with Devialet support. They have so far asked me to assure that my Dialog is on DOS 2.
I checked this by re-adding it to my setup in the app.
In the app I can choose Dialog as optical input (like before), but nothing happens when I choose it. I can also choose left and right Phantom.
When I return to the main screen, it says No cable optical left. It does not react to my selection of "Optical (dialog)" under source selection.
As soon as I remove the optical cable from the Dialog and put it into the left phantom, the sound is back.

It does not seem to transmit sound from dialog to Phantoms via PLC, but I have no indication from the Dialog on what should be wrong.

It will be a lot of work for me to put in new optical wires in the wall that carries the Phantoms, but I think I will do it and throw away the Dialog that is of no good.
Even if the Dialog did work for me - is there anything I can only do with it?
Does it provide something that my Phantom does not, like Airplay 2, or?
What is the difference between optical in dialog and optical in Phantom.
Difference in delay perhaps?

Thanks,
Jacob

[quartz78]

hi @jacob
they will also ask you to check that all your devices are on the same, latest, DOS version (2.9.0) and that you have the latest app, too. Also worth checking out: is Dialog light white? and not blinking? And they will ask you to send a report from the app if everything else fails (should be sent when you are experiencing the issue). You should continue pushing them to get to the bottom of this.

Now, the hardware in the Dialog is bound to be different from the one in the Phantoms, so it is possible that you feed a stream that is recognized by the Phantoms and not by the Dialog. Sadly, no list of the supported formats is provided by Devialet, so it is kind of trial and error. It may even be that on the same model manufactured at different moments, the supported formats are not exactly the same. I recommend testing in plain PCM, 44.1 / 48 at 16 bit, to maximize chances of success. Do not try to use Dolby or DTS streams.

Why use Dialog at all? Good question. As a third optical input, the one which is not necessarily at the same physical place as the Phantoms. Or, if you have a very old Phantom without AirPlay, a Dialog (with MFI chip) will allow you to play AirPlay. On newer Phantoms, it does not matter. The difference between optical in dialog and phantom? Normally, none. But as I said, the list of supported formats may not be the same, and it appears (see other posts in the forum) that the latency on the Dialog is actually worse than if you use optical input on the Phantom directly, due to a firmware bug. I think, for a stereo pair, feeding directly into a Phantom makes more sense, if you can allow it aesthetically, because then the signal goes through the network only once instead of twice. Also worth noting: the Dialog does not have advanced settings for latency and network interface, as the Phantoms do. So, less possibilities for tweaking your connection here.

[jacob]

hi @jacob
they will also ask you to check that all your devices are on the same, latest, DOS version (2.9.0) and that you have the latest app, too. Also worth checking out: is Dialog light white? and not blinking? And they will ask you to send a report from the app if everything else fails (should be sent when you are experiencing the issue). You should continue pushing them to get to the bottom of this.

Now, the hardware in the Dialog is bound to be different from the one in the Phantoms, so it is possible that you feed a stream that is recognized by the Phantoms and not by the Dialog. Sadly, no list of the supported formats is provided by Devialet, so it is kind of trial and error. It may even be that on the same model manufactured at different moments, the supported formats are not exactly the same. I recommend testing in plain PCM, 44.1 / 48 at 16 bit, to maximize chances of success. Do not try to use Dolby or DTS streams.

Why use Dialog at all? Good question. As a third optical input, the one which is not necessarily at the same physical place as the Phantoms. Or, if you have a very old Phantom without AirPlay, a Dialog (with MFI chip) will allow you to play AirPlay. On newer Phantoms, it does not matter. The difference between optical in dialog and phantom? Normally, none. But as I said, the list of supported formats may not be the same, and it appears (see other posts in the forum) that the latency on the Dialog is actually worse than if you use optical input on the Phantom directly, due to a firmware bug. I think, for a stereo pair, feeding directly into a Phantom makes more sense, if you can allow it aesthetically, because then the signal goes through the network only once instead of twice. Also worth noting: the Dialog does not have advanced settings for latency and network interface, as the Phantoms do. So, less possibilities for tweaking your connection here.

The funny/tragic thing is, that the delay with dos 1 +dialog by coincidence exactly matched the delay in video through my wireless hdmi-to-projector setup. This is not The case with dos 2 + phantoms.

[quartz78]

@jacob I presume the latency is higher now? Because otherwise, you can always add the extra latency in the "latency" settings in the app.

It is unfortunate, but anything wireless inevitably adds latency. If it is a major problem for you, I advise full Ethernet setup + setting the latency to the minimum in the app (minimal latency will most likely not work through Wi-Fi).

It is also possible to compensate for latency when streaming in AirPlay. Only some sources will do it, though. I know that AppleTV deals well with the latency, delaying the video by the appropriate amount of time. On the other hand, I doubt very much that this "smart latency correction" will work if you AirPlay YouTube content from Safari on a Mac. Then again, using AirPlay on a Mac is a vast topic and the results may be wildly different depending on whether you use AirPlay on the system level (top bar) or directly from an app (such as iTunes).

[jacob]

@jacob I presume the latency is higher now? Because otherwise, you can always add the extra latency in the "latency" settings in the app.

It is unfortunate, but anything wireless inevitably adds latency. If it is a major problem for you, I advise full Ethernet setup + setting the latency to the minimum in the app (minimal latency will most likely not work through Wi-Fi).

It is also possible to compensate for latency when streaming in AirPlay. Only some sources will do it, though. I know that AppleTV deals well with the latency, delaying the video by the appropriate amount of time. On the other hand, I doubt very much that this "smart latency correction" will work if you AirPlay YouTube content from Safari on a Mac. Then again, using AirPlay on a Mac is a vast topic and the results may be wildly different depending on whether you use AirPlay on the system level (top bar) or directly from an app (such as iTunes).

Support asked me to verify the DOS version of Dialog. I confirmed that it was latest version, and re-added it to my seutp in the app.
But not nothing happens when I select the dialog as optical input. As alway, switching the optical cable from dialog to left phantom works immediately.

I tried from an iPhone that ran the newest iOS to see if it might be my old iPhone. Same thing. 

I have now gone through the pain of partly disassemble my wall and installed an optical cable to the left phantom. Since my previous setup was powerline to phantom only, it was aesthetically perfect, with a single white cable from the wall to the phantom, with the best way to fit this. See picture.
It was remarkably hard to plug in the tos-cable to the back of the phantom when actually hanging on the wall. Since the tos-cable has limited lenght at this point, it need to be fitted when the speaker is in position. Almost impossible....

Now I have an obsolete Dialog if anyone should be interested.

Cheers,
Jacob