Yes, I quoted that. I have never owned a BD player with an HDMI input, so have no experience with that. Yes, an MHL device will connect to a standard HDMI port, but there's no certainty that it will work correctly. That's why I'm asking if you are using an actual MHL port. Looking at the manuals online, it doesn't appear your TV has one, the Oppo front port is MHL capable, but not the rear one, and your Yamaha shows MHL support on the front HDMI jack but none of the rear ones. Just confirming it's one of those.
Nvidia Shield, Roku Stick (3600), and Ultra (4640), Insignia Roku TV, Sharp 4K Roku TV, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network. Samsung JU7100 4K TV, Yamaha RX-V583, CenturyLink DSL