The PWM setting has several selections in increments of numbers and at the bottom there is a Outrunner Mode and that's where I have it set since my motor is an outrunner. I see what you are saying about the cutoff voltage, I will tinker with as well. But I think I was tinker with all of the settings today since it's been narrowed down to the esc.

I test it yesterday afternoon even fly it 1-3 ft, it hover right, it doesn't drop, i mean drop on 1ft flight and hit the ground, as it does before, after replacing the main gear and lube the bearing of the blade grip.
Baurwin you maybe right regarding lvc, as it did that to my heli long time ago, but it will drop only when the esc sence low voltage or if your battery is not charge, or after flying ater est 9 min of sport flying also depend on your battery mah and flying type.
Squawk7700, is your tail grounded, maybe it causing glitch on the tail. Some pilot grounding their tail even they are on 2.4 radio, check you tube regarding about it, as i did some research before about glitch causing heli to drop, it happen on mine last year.

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Had same sort of problem it was the outer swash plate ring moving up and down caused 2 crashes and many parts. Ca ring back in place and my trex is happy once again. Might not be the problem but this condition caused erratic heli opperation.Did not even wait for the new swash to arrive, and when it does will inspect , the old swash came out of the box new, only 10 flights on align trex. hard lesson to learn

I am very new to this but have had this issue also. i would hover the heli fine and then the next day when i started up, i noticed a tail wag. i could still hover but had to correct for the tail wag. I then started to loose power and was unable to throttle up. when 450 landed, i could immediately throttle up and get it to hover again..this was repeated at 2',4',6'. It happened at all heights. I finally landed and removed the canopy. The esc was hot to the touch and the motor was not much cooler. This is stock align 35amp and 430xl motor. I read forums and decided it could be the esc. I took it to a local hobby shop and this was confirmed. I had an esc kicking out. So i replaced with a CC Thunderbird 54amp and Scorpion 2221-8. This should solve my problems for awhile.</p>


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Rick</p>

Well funny you should say that. After approx 25 flights my problem is back. But it does not happen all the time. When it starts acting up, it suddenly drops 2' to 6' . I land take it in side and recheck everything, find nothing apparntly wrong, put another batt in and it works fine for awhile. I think I will try a new esc very soon!!!

I had a similar problem with my fp, rotor speed would cut out then come back. The throttle potentiometer on my transmitter had a dirty spot. Get a can of contact cleaner at radio shack and spray a very small amount into the throttle pot inside your radio (it may be hard to a find an opening to get the stuff to spray inside) then move the stick for a few minutes.