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agentmouthwash said:

audio hijack pro is great. i always recommend it. i've not used wiretap so can't really compare.

AHP does aiff, mp3, aac, and apple lossless. it can schedule times to record. record from any application. it pauses recording when audio stops and continues when sound starts again. you can split audio files during recording. it supports audiounits. great podcasting support.
 
I wish that I would have downloaded Audio Hijak when it was free, that way I could have it right now.
 
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