This morning I listened to some WAV files via Oppo 203 with hdmi output to my Marantz AV8801 AV preamp. I was not that happy with the results. Pretty flat sounding. I was curious about why and searched online for possible reasons. Then I read this article: A Deep Dive into HDMI Audio Performance Basically the author did measurements and it seems generic modern commercial AVR do not handle HDMI well. I wonder if my Marantz is pretty much the same in handling HDMI. The author then suggested using SPDIF for critical listening. May be I should try SPDIF out of my Oppo? Any other suggestions? Thanks!