Also Check that 524 device if there is any new Updates for it from infomir.
I did see one person report they had an update and that fixed the Block... I don't recall exactly though.
Not much hope for the MAG 254 though, as big mac mentioned.
checked setup all ok been running 10 years strong just for the hell of it I did a Manuel update and sound came back at least two of them back up now to figure my mag 524's