Best way to do timeout prompts?

Question

I'm using MX 2004, and I need voiceover timeout prompts.
What's the best way to accomplish the timing? I've used
onEnterFrame to count down some timers, but, but I've had mixed
results - they don't have to be too accurate, just working with
some predictabillity. I'm also concerned that using onEnterFrame
may slow things down too much.
I tried to use setInterval directly, and have the interval
clear itself, but it didn't. I also tried Senocular's setTimeout
function that uses setInterval, but it only runs once, same kind of
thing I tried in simpler form. I tried different things and now I'm
all confuzzled - sometimes they work and sometimes not. I should
probably start from scratch (again), but deadlines are looming and
I can't think straight anymore - I'm just kind of thrasing around -
I also tried a "do nothing" loop, but then I get a "slow script"
warning.
I think part of the problem is that I have some voiceovers as
prompts and they aren't finished by the time the interval is
cleared. I preloaded them into a swf and am loading the movie that
way.
Advice is greatly appreciated, TIA!

Answer 1

I came across your suggestion to clearInterval before
setInterval (in several threads), so I started doing it. I'm also
using stopAllSounds() when a button is pressed.
This is how the sounds are loaded: in frogAudio.swf, a 1
frame swf, I have the sound files in the library, then do this:
_root.l2vo1=new Sound(this);
_root.l2vo1.attachSound("L2_VO1.wav");
Then in the first frame of the movie, I have an empty
audioHolder_mc, and load the file with:
_root.audioHolder_mc.loadMovie("frogAudio.swf");
T