I'm facing the same problem as this guy (whom I found by googling): No sound on HDMI through a Pioneer VSX-527, works if connected directly to the TV - Ask Ubuntu
Basically, my PC (Ubuntu Server 14.04) is connected to my receiver (Pioneer PSX-527 - detected as "Pioneer Electronic Corporation 72"") via HDMI. Both the TV and the receiver supports 4K resolution. I can however not get any sound if I set the resolution to 1920x1080 and the refresh rate at 60 Hz. In order to get sound too, I have to go down to 25 Hz.
My CPU is a Intel(R) Core(TM) i3-3225 CPU @ 3.30GHz and I'm using the built-in graphics chipset.
How can I get sound to my TV at 60 Hz? Is this even a driver issue, or is my receiver simply not good enough?