High bitrate AAC on iPod 5.5g

[trudslev]

Hello there,


I have just installed Rockbox r16441 on my iPod Video 5.5g. Generally it seems to work fine, but I am having playback issues with all the files I've ripped using iTunes.

They are in AAC format, 320 kbps. When they play they are highpitched and fast (setting pitch to 100% does not seem to change this), and they skip about 3 seconds every two seconds of play back. Changing the playback buffer does not seem to help this.

These files play back fine using the original firmware.

Is there anything I can do (like other codecs?) or anything.

Any tips will be greatly appreciated.


Regards,

Sune

[zajacattack]

Have you tried a lower bit rate? Sometimes AAC files that are long and/or very large have trouble playing in rockbox.

[trudslev]

Yes, my point is, I don't wish to have to rerip 3000+ songs.

[saratoga]

If the pitch is off its probably not bitrate, but some other problem with the files.  What sample rate did you use?  

[trudslev]

iTunes was set to the "high quality" which has sample rate to auto. But when I look at the encoded files they are set to 44,100 Hz.

[saratoga]

iTunes was set to the "high quality" which has sample rate to auto. But when I look at the encoded files they are set to 41,100 kHz.

Do you mean 44,100 Hz?  

Could you screen shot the file properties dialog box in foobar2000 or some similar app that can give MP4 stream info?

[Lear]

I encoded two files using iTunes 7.6 set to 320 kbps AAC, and they play fine on my Sansa e200 (though the boost ratio is high), so I'd expect an iPod Video to be able to handle it too (at least after buffering is complete). However, the high pitch suggest Rockbox is not parsing the files correctly. If you can send me a (preferably small) test file, I'll take a look at it.

[trudslev]

Do you mean 44,100 Hz?  

Could you screen shot the file properties dialog box in foobar2000 or some similar app that can give MP4 stream info?

Yes, I mean 44.1 kHz.

Well, I guess looking at foobar2000 shows I didn't use iTunes to rip this perticular CD. It's only 192kbps too. But this is one of the files I am having troubles with:


I have sent a link for that file for Lear, so hopefully he can see what the problem is.

[trudslev]

Well, apparently it was a brain fart on my behalf (as expected by me). The file is a HE-AAC file, and not created by iTunes. I'll re rip it a proper format.

[senab]

192kbits HE-AAC, are you mad? You shouldn't really use HE-AAC for anything over 80kbits.

[trudslev]

I'm not sure how it happened. It was just supposed to be regular AAC.