[UPDATE] - additional information and clarifications.
I'm having a fairly consistent issue with the last two server betas (including 3.0.5188.21314) Where, when streaming, several blu-ray ISOs play (it seems) whatever the #2 audio stream is and incorrectly states it is playing the primary (English) audio stream when the english stream is an HD audio stream (e.g. DTS-MA). Switching streams seems to have the same issue, and critically, there appears to be no way to actually select the primary English stream either before or during playback.
I've tested this in the web interface and XBMB3C (in streaming mode) and behavior happens across a number of BD ISOs with multiple audio streams and an HD primary stream. Note this problem does not appear when directly accessing the file system - MBC and XBMB3C both play the expected English audio track for my BD ISOs. Additionally, DVD ISOs play the expected audio track both locally and when streaming.
Happy to provide any additional information upon request!
Edited by Buckaroo, 17 March 2014 - 04:05 PM.