Okay this is where my technical knowledge ends but must be the type of audio/video of the stream I'm trying to watch? If this is the case, two possible routes:
(1) Change a setting (quite likely as I tweaked a few to make my audio work - I use a SPDIF to my surround sound), but what do I need to change?
(2) Maybe this new box can't handle the stream (doubtful as it is a new S905 and my old RK3288 was fine) but how would I test this/what do I look for?