I've had my UFX since Feburary, and it does the exact same thing as the video posted on the other thread you linked to.
It did not do it the very first time I turned it on, but it does do it if the unit is powered off long enough to cool down.
The sequence to reproduce on mine is as follows:
Leave the unit powered off for several hours.
Turn the unit on (does not need to be hooked up to computer). I also leave my speakers off until the warm up problem is finished.
After about 30 - 60 seconds the popping will start, and will last 15-20 seconds.
Once the pops dies down I can turn on speakers and everything is fine.
If I turn the unit off and back on in a short amount of time ( < 10 minutes), the pops don't happen.
If it's allowed to cool off, (> 1 hr.) the pops will happen.
For this reason, I rarely turn of my UFX unless I'm packing up for a gig.
I suspect the problem has something to do with the digital control of the pre-amps. If you watch the mix software levels, you see the pops comming in only on the 8-12 channels that have preamps.
I've been thinking about creating a mix that has all of the preamp channels and master levels completely off, and trying to save that as a mix to boot up with (not sure how yet).
Overall I've been very happy with my UFX. My only complaints are this one issue, and that the thing runs so darn hot. I can't imagine why it generates so much heat. I do like the fact that the power supply is built in, but would it maybe not generate as much heat internally?