XBox One dual output for cinema projection- HDMI video, AV audio

Hi Enfynet,

The Xbox One only has 1 HDMI out. The only way to use a dual out would be to have an HDMI splitter of some sort. Using a splitter you'd be able to supply video to each of your devices. If your device doesn't use HDMI, I would recommend getting with the
manufacturer of your video device, and seeing if there was a compatible HDMI to (other video type).

The reason why the regular AV cable is designed to block the HDMI port is that the Xbox 360 cannot output analog video and HDMI at the same time. The differences in between the supported resolutions and the limitations on outputting some video content in
analog HD means they have to shut the analog video output off when HDMI is connected.

There is only one use to having both connected on a traditional Xbox 360, which is using the optical audio output of the old-style AV plug to get 5.1 audio on non-HDMI receivers while sending the picture over HDMI. With the newer Xbox 360 S, this is not necessary
as it already has a dedicated optical audio output on the back. The newer-style AV plugs also lack an optical output from what I know.

If using the regular AV cable this way, there are some problems that can occur. The AV cable identifies itself as such using ID pins in the connector. When the Xbox 360 senses this at the same time as an HDMI connection is active, it gets confused. If the HDMI
connection is dropped - for instance by temporarily switching over to a different input on the TV - the Xbox 360 reboots and starts outputting analog video instead. It may also prevent the Xbox 360 from establishing an HDMI connection when booting up, unless
the TV responds instantly.

There used to be an official audio adapter sold to get optical audio out of traditional Xbox 360s at the same time as HDMI. Those had their ID pins connected to identify themselves specifically as an audio-only dongle. This avoided the Xbox 360 rebooting if
it temporarily lost the HDMI handshake. However, they are no longer made by Microsoft. There are unofficial third party ones, but their ID pins may be wired like the regular AV cable and cause the same booting/rebooting problem.

So if you want to swap between HDMI and regular AV output, the only solution is to plug in only one at a time. If you need separate audio out, try to get hold of an audio dongle that's been proven to work correctly - which may be a bit tricky.

You need the thin AV audio adapter that comes with the original HDMI AV kit. You can usually find used adapters on eBay or perhaps even at GameStop. The adapter provides left/right audio as well as optical audio while enabling the HDMI port for video.



Devices plugged into the AV port determine what video output the 360 uses. Wedging a regular AV cable with video into the AV port, alongside an HDMi cable, confuses the 360, disabling HDCP. This may be causing the monitor sync issue you're experiencing.

There is a problem with many third party audio adapters in that they're wired to identify themselves as a full AV cable to the Xbox 360. The original audio adapter which is no longer in production, was wired to have its own unique identity.

So in a nutshell, the Xbox 360 thinks it's supposed to be sending composite video over the AV output, not just audio.

And this highlights a limitation to how the Xbox 360 handles video output. For technical and some licensing reasons, it cannot output HDMI and analog video at the same time.

When the Xbox 360 boots it prioritizes HDMI and tries to establish a connection with the receiving device. If there is no response, it instead checks if there is anything connected to the analog AV port and if so, switches over to analog video output. If nothing
is connected to the analog AV port, or a properly wired audio adapter, the Xbox 360 simply keeps on waiting for the HDMI connection to establish.

The same thing happens if the communication over HDMI is interrupted. If there is nothing connected to the analog AV port or a properly wired audio adapter, the Xbox 360 waits for the HDMI connection to re-establish. If there is an analog AV cable connected,
it reboots so that it can configure itself for analog video output.

To solve the problem, you either have to crack open the audio adapter's connector and re-solder it to make it identify itself as an audio adapter, not as an AV cable. If you have a soldering iron and want to take a crack at this, you should be able to find instructions
on the net for which pins to wire.

Another soloution is to try getting hold of a used original audio adapter, or a third party one that is known to be wired correctly.

Of course the most dramatic and expensive solution is to get an Xbox 360S. As stated by Bill Gates in an interview once: "Microsoft has never been accused of not knowing how to make money".

Eh, your "solution" isn't ideal.



AV port cables are pinned to tell the 360 how to output video and audio. While cracking open cables works sometimes, you're left with an HDMI output that doesn't support HDCP and potentially display resolutions listed as X by Y, not HDTV standards.



The proper thin AV audio adapter that sits alongside HDMI cables tells the 360 that audio can go via the adapter and video goes via HDMI, retaining HDCP support and allowing the HDMI port to properly handshake with attache devices.