found this thread and although it is a bit old, it is the only thing I can find that applies to my problem.
I have a B650 and have tried to find a way to stream the media I usually play. I have tested all settings in PS3 Media server but have the same problem as you describe, i.e. accelerated video and no sound when playing mkvs of 24fps. I appreciate the bypass you found for streaming the mkv to the tv untranscoded, but problem is that most of the material I have is DTS so I really want it transcoded to ac3 if it is possible...
Did you ever found a solution to this? Or are you using some other server? Or if is it impossible to get working by changing the settings someway, maybe somebody can recommend another good DLNA server that could transcode properly to a Samsung? The best I have found so far is a russian server (homemediaserver.ru). This server looks really amazing with its number of settings however the slight problem is that it is in russian
But once you get a bit hang of the cyrillic alphabeth it is actually possible to understand most of the settings
The transcoding to the Samsung of 24fps mkv with dts works good except for that it always stops playing after about 10 minutes for. I suspect that could to do with the server reporting wrong length of the stream to the tv but I have not managed to find a setting to change this.