The list of supported encodings seems to dash many hopes that what you have will play. Let's use THIS FORUM and what folk discover. Ready? HDTVs are not PCs. The codecs are limited and even if you find AVI, MP4 and MKV in the supported list it is still possible that the person that encoded the file to do it in a way that the HDTV can't play it.
EASY TO FIX. Re-encode with an encoding that works.
Bob
Hello,
I am interested in buying this Blu Ray player, but before that I would like to know about a few issues.
1. When a movie (mp4 5.1 audio) from a usb drive is played, does the player output 5.1 channel audio or normal stereo. The player would be connected to a onkyo receiver (supports all latest codecs) via HDMI and receiver to LCD TV via HDMI.
2. Does the player support subtitles for media files (mp4, avi, mkv)
3. Does the player supports wav files.
I request somebody to reply to this questions as I am badly in need of this player.
Thanks,

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic