Rogue Amoeba Software has released Audio Hijack Pro 2.1, a free update to its audio recording/enhancing utility for Mac OS X. Version 2.1 offers several new features, including a new Channel Tweaker plug-in, Sample Rate settings in AIFF recordings, variables in recording ID3 Tags, and 800×600-resolution compliance. In addition, over two dozen bugs have been fixed, including issues with AAC recordings and many others. The full version of Audio Hijack Pro sells for US$32.