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So, if I understand this correctly, the ogg files created from the FLAC files using foobar, with tags copied from the FLAC files, fail in your portable.
Correct
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The ogg files created from the FLAC files using oggdropXPd are read fine in the portable, but do they contain tags, or not?
They don't contain any tags.
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The fact that removing the tags from the ogg files doesn't solve the problem may suggest that the tagging routines in foobar are behaving in a way that is not quite standard, or if the oggdropXPd generated files aren't created with tags, then there is something about tagging that the iRiver doesn't like.
Yeah, that's the question isn't it?

Anyway, I'm glad to find out it probably isn't a bit-stream problem. This is the first time I have encountered this problem and I have done a lot of conversions with both foobar and oggdropXPd. But as a previous poster suggested, it might have something to do with the new 1.2.0 libvorbis. I haven't used 1.2.0 until now (there was no reason to) and since aoTuVb5.5 is using 1.2.0 that might indeed be the problem. Luckily, there are workarounds for me.

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I'll test with libvorbis 1.2.0 later today and let you know if the problem is still there.
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