latency tests as part of set up
Ableton Live has a nifty feature during set up -- it simulates a CPU load and then plays an A440 tone while the user adjusts the buffer size until the pops and crackles are gone (or start, depends on which end of the buffer size slider one starts on). The user can also alter the percent CPU load to account for plug-ins etc. and rerun the test to optimize the setup for the particular combination of effects, etc.
Takes a lot of the guesswork out of the set up.