Why is AAC audio playing as MP3

My streamer can play AAC.
But when I play an AAC audio stream (Radio Paradise 320k AAC (Europe): http://stream-uk1.radioparadise.com/aac-320 ) it plays as MP3/320.
I cannot see in the profiles where audio AAC is being transcoded etc.
AS this stream is aac/320 (i.e. higher than mp3/320) it would be better to play as aac (or LPCM).
How/where is audio AAC handled in the profile?
But when I play an AAC audio stream (Radio Paradise 320k AAC (Europe): http://stream-uk1.radioparadise.com/aac-320 ) it plays as MP3/320.
I cannot see in the profiles where audio AAC is being transcoded etc.
AS this stream is aac/320 (i.e. higher than mp3/320) it would be better to play as aac (or LPCM).
How/where is audio AAC handled in the profile?