Feeding audio into HDMI

[Dave Plowman (News]

My setup in the workshop is a bit weird. This old Acorn and a modern PC share a monitor - DVI input - via a DVI KVM switch. So all the video is DVI, and works just fine.

I have a splitter in the monitor feed which gives DVI and HDMI outputs which can both be used at the same time. The HDMI feeds the TV over the workbench. To save extra cabling, it would be handy to feed the PC audio to the TV too. And on from there to the sound system.

I bought a DVI to HDMI adaptor with a USB connection for power and audio. But plugged into the DVI/HDMI splitter stops the TV video working. All the resolutions are fine - normal HD.

[Andy Burns]

DVI to HDMI are usually just a passive adapter, since it's all LVDS anyway, suppose it needs to be active to do the audio, I have a VGA to HDMI, which claims to insert audio, but I've never tried.

Interfering with HDCP? you can buy HDMI audio inserters

[Dave Plowman (News]

That's what I'm using - badged StarTech. DVI in, HDMI out. Powered by a USB lead that also gets the audio from the PC.

My DVI splitter in the monitor feed was DVI to DVI and HDMI, which worked perfectly. I swopped over the outputs to the monitor using an HDMI to DVI cable - and that worked. Leaving the DVI free for the DVI to HDMI + USB. But no signal to the TV.

[Theo]

HDMI has a legacy fallback mode that's compatible with DVI - this mode doesn't do audio. Full HDMI does.

I suspect the DVI to HDMI adaptor is converting the DVI video stream to kosher HDMI, which the DVI switch now can't handle.

Does the TV have a spare HDMI port to wire in the output direct?

If not, HDMI splitters/muxes are about a tenner on Amazon. The bonus is the cheap ones also strip HDCP, because doing the proper copy protection is too expensive for their price point. So they simply output unprotected video.

(most of those have port selection via either a button or a small remote control, rather than any keyboard input)

Theo

[Dave Plowman (News]

I know it's very confusing, but the DVI to HDMI+ audio is after the KVM switch, in the monitor feed.

I've already installed an HDMI cable to it. Which worked perfectly, vision only.

I'll summarise again. Both computers have DVI-D outputs. The KVM is DVI-D. The monitor DVI-D only (no HDMI) I have effectively a second monitor duplicating the first - but it's a TV with HDMI only. I have a splitter in the monitor feed - DVI-D in, DVI-D and HDMI out. That all worked perfectly. But it would be nice to have the sound from only one of the computers available at the TV. But do need pictures from either. It can't be that hard, can it? ;-)