I never had a problem with my very old Audigy 2 ZS card, until recently where I started to make use of Dragon Naturally Speaking where I need the microphone input.
I am using the "latest" official Audigy 2 drivers from creative, but the same problem happens with Audigy 4.5 (Daniel K) support pack or Pax Drivers.
The problem is that approx. 1 in 10 times when the sound card initializes the sound from the "mic input" is fluttering/stuttering. (It's like a 20 hertz stuttering while recording sound from the mic. Disabling/Enabling the mic usually solves the problem).
It's annoying since I never know whether my mic input works before I work with Dragon Naturally Speaking, I always need to verify whether the stutter appears before I can start work.
I already used DPS latency checker and and similar but have no idea what may cause the problem.
KX drivers (as an alternative to creative drivers) are likewise not working since they crackle and distort sound greatly.