The LineIn page says: > New in 2.3: A long-standing issue with latency in LineIn has finally been cured! We've also added a menu item for toggling play-thru.

The LineIn page says: > New in 2.3: A long-standing issue with latency in LineIn has finally been cured! We've also added a menu item for toggling play-thru. I'll try it out.