Guess this is as good a place as any...
I've got a Monitor Audio A100 "integrated amplifier," commonly used as a receiver, which has a simple IR remote. Tried to set it up as a receiver, but despite the Xbox One knowing the Monitor Audio brand, it didn't know what to do with the model. Not sure if requests are taken, but if they are, I would like to request that this model make it into the next batch/update for receiver support.
If it helps, emailed Monitor Audio and they said the IR codes are as follows (in the context of setting up with a universal remote)...