I just bought a brand new Mac about a week ago, I also just recieved the update for the new OS (Leopard). Now I am importing CD's into iTunes at 128 kbps AAC and there are bit rates coming up like 127 kbps and 133 kbps. Variable bit rate is unchecked, i redownloaded iTunes after updating my OS and am still expiriencing this problem. Previous to Leopard I never had this issue! HELP!
I'm having this same issue so I started to look into this. This is what I have found so far:
If you have old imports (done before Leopard) in let's say 160 kbps AAC without any VBR, they still display the bitrate as 160 kbps in iTunes under Leopard. But if you go to the Finder and choose Get Info command, then you will see the actual bitrate which might vary from 158 to 160 kbps. So even before Leopard, the bitrates haven't been that consistent. iTunes under Tiger has simply been showing them as 160 kbps AAC, as I think it shoud be.
If you import those same songs again under Leopard with iTunes 7.4.2, then iTunes will show the exact bitrate that those files have. But to make things bit complicated, now the bitrate varies much more. Under Leopard they vary from 152 to 162 kbps, all this without VBR setting being used. So you get much more varied bitrates in Leopard.
However, if you choose to use 160 kbps AAC and use VBR, then the bitrates vary from 159 to 167 kbps, giving you higher quality and larger files sizes.
You can make your own conclusions from what I have found, but I wish iTunes under Leopard would give me more consistent bitrates when I'm not using VBR. And display them in iTunes with bitrate I chose without using VBR.
Actually, apart from the negligible differences in audibility (which I'm not concerned about), it is important that this issue is fixed.
Quite apart from problems in creating smart playlists based on bit rate, consider: certain programs depend on bitrates being the same in order to work. I use a couple of utilities which losslessly join together AAC files, but they
have to be CBR in order for the join to work. The old iTunes obviously produced files which matched closely enough, the new one doesn't. Since we have a VBR setting already there for those who need it, it is palpably perplexing why the behaviour of the CBR setting has been changed.
Just updated to iTunes 7.5 and the problem still there. I usually rip 320 AAC. I have sent a feedback already on the 26th when I noticed the problem, I guess we have to wait. Cheers
The same problem is happening to me, but I haven't upgraded to Leopard. It only started when I auto-downloaded the latest iTunes update 7.5. What's going on?
iTunesJoin's lossless joining of AAC files depends on their being CBR. Prior to this version of iTunes, this worked fine. The new "CBR as VBR" functionality has destroyed this lossless joining of tracks.
