[mythtv-users] audio issue - HDMI tv

[Alasdair Macdonald]

I'm a bit confused by your description of what device is connected to
what other devices, and how, but it sounds to me like a CEC issue.

CEC is the HDMI feature that allows control messages to be sent along
with the HDMI data, eg to switch on a linked device:

https://www.howtogeek.com/207186/how-to-enable-hdmi-cec-on-your-tv-and-why-you-should/

If I understand correctly, when it is powered, your TV is trying to
enforce use of the HDMI cable / device to which it is connected.


On 26 March 2018 at 11:44, Tim Draper <veehexx at zoho.com> wrote:
> While strictly not a mythtv issue, it is to do with one of my FE setups.
>
> my conservatory has in-floor speakers by the previous owner and figured i could use them with an external amp (ebay/amazon Lepy T-class amp). This works fine from my phone/laptop.
> It doesn't work when i have the 3.5mm jack connected to my rpi3 AND is connected to the TV with HDMI cable. even with the rpi3 unpowered, the lepy amp seems to see some sort of fault and (i think) enabling & disabling itself every few seconds. - internal relays clicking and speaker popping as it switches. disconnect either end of the HDMI cable form the rpi3 and the issue goes. Plug rpi3 power in and problem remains. swapping HDMI cable has same effect.
> problem occurs both on the rpi3 3.5mm jack and a USB sound card.
>
> i'm not really sure exactly what or how, but something in the TV is upsetting the external amp. happens with the tv on, soft-off, or turning the physical switch on the side of the tv off. only way to stop it is to physically unplug the mains cable.
>
> TV is a 2009-era LG 32".
> Is this a case of i'm outta luck or is there something i can do to stop it? I've tried to disable the tv speaker via the menu and cant see anything else in there that could help.
>
>