Hi,

For testing purposes, I tried using foobar2000 to convert an MPEG-4 audio file downloaded from http://yoz.com/files/aacplus/ to AAC, to use on my personal audio player which needs "raw" AAC files. (URL was found when searching Google for aacplus.)

I'm using an O2 Digital Music Player (DMP) which is, as far as I know, the first/only personal audio player which supports HE-AAC (aacPlus).

When I try to play the converted AAC track on the DMP, the player shows elapsed time as 91:23 and total time as 82:47, and plays no sound. Is there something special/odd about the MP4 track available at the URL above? (I can't play it on my computer, for two reasons: I have no sound card, and the PC is probably too slow to play AAC audio at all. Really!)

Tracks ripped from my CDs and encoded using aacenc32 (and the Nero AAC DLL) play fine on the DMP. Also, I can use foobar2000 to convert those tracks from AAC to MP4 and back again, and the resulting files play fine on the DMP too.

Properties of one of the downloaded MP4 files:
bitrate = 48
samplerate = 44100
channels = 2
aac_profile = HE AAC
codec = AAC
tool = Nero AAC Codec 2.6.1.9

Properties of the downloaded file after conversion to AAC:
bitrate = 49
channels = 2
samplerate = 44100
aac_profile = AAC HE
aac_header_type = ADTS
codec = HE AAC

Poperties of an AAC file created from CD (which plays fine):
bitrate = 115
channels = 2
samplerate = 44100
aac_profile = AAC HE
aac_header_type = ADTS
codec = HE AAC
and the ID3 tag info.

So they *appear* to be in the same format, but one doesn't play on my DMP.

Has anyone got any idea to what the problem might be?


-- M