I'm just looking at doing the same thing - i.e. I have Integra DTR 7.8, I want to add a 4K TV. The TV I'm looking at has Audio Return Channel on an HDMI port, so it seems to me I can run HDMI audio out on this, and run it into an HDMI In port on the Integra, then I should get all audio formats through to the Integra. Any comments as to whether this will or won't work ?
It will work, but only to a point. The HDM audio return has the same bandwidth as Toslink or coax SPDIF. That bandwidth is not enough for the loss less codecs.
This is the problem with 4K. It produces a no meaningful picture improvement, but unless you are basically prepared to replace a good deal of your equipment and likely cables, you are headed for a very definite audio downgrade.
While I like having a picture with my audio, audio performance is paramount. I'm very happy with my rig, and have no intention of re engineering it for a 4K TV that will give a poorer picture than the Panny Plasmas I have now.
I have a strong suspicion that this whole thing was a marketing ruse of marginal if any benefit to the consumer to generate unnecessary equipment sales.
If you do buy a 4k screen and can bet you will end up with more negatives than positives.
I'm smart enough to steer well clear of this industry ruse.