This is a problem I've had since I bought the AIOS back in April 2012! The Aios will play all the audio formats with any of the R19, R20, R21 and the 3432 beta!
About 2 times a month it will not play the HD Audio (dolby THD 6cl and dolby THD 8cl) thats what it shows under the Audio on the AIOS! I really think this player has a mind of its own! It will play great and then one day it won't play the Audio tracks I've stated! I then have to use the up-date on the USB and everything is back to normal!
With the new R21 I just have to use the AIOS reboot and that worked until yesterday, but then I used the USB (R21) and things are back to normal!
This is almost the end of the month so it won't do it again till next month, at the beginning and close to the end of the month! You might think I loseing my mind, but I'm not! For 7 months now I've seen it do this twice a month every month! I think theres a GREMLIN inside of it, really, not trying to be funny!
I don't have no clue why or how this happens or any solution on how to stop it! If I take it with me where ever I go I carry a few pen drives with me, R19, R20, R21, and the beta34! One of them always works!
I also have updated both ways, normal and hard boot and it works just fine!