Any crashes on the Heli/Spirit where the glue may have fixed a loose connection or board ?

Well i can't say...like i said in the begining, this unit's been on this heli for over 1300 flights and about 15 crashes. Spirit took all w/o any visible or noticable damage, thats all i can tell.

did you log the vibration level of your flights? it could be interesting to see vibration level of the model in warm and cold ambient. i was one of the few that had similar problems with the first 3.0 release on (only) one heli, that later showed to have a bad tail bearing causing serious vibrations... that where even worse in cold weather (which is clear, as every metal and plastic of the heli is stiffer in cold ambient and therefore less dampening). it rescued fine above 10-15°C and seriously bent below 8-9°C. the longer the flight (and colder the heli) the more bent.

in my case 3.1 solved the problem and - of course - the replacement of the bearing

... Stabi Correction can be sensitive to vibrations...

_________________
cheers
Michael

No i haven't logged in flight vibrations.
Only vibrations on the bench with no blades (as per manual instructions), and those are quite low on all axles - Y being the worse one with combined value around 25, with main rotor spike at about 50 and tail rotor at 40. While X and Z are really small. Ran @ 3600rpm head speed.

I'm not sure whether I could record in flight vibration log, bcs i use only 6ch radio, and i have all 6 used (tail gain, rescue). And as far as i understand, you need another channel to activate in-flight vibration recording? And besides that, i dont bring a computer when i go flying and neither have BT module, so i believe i would have to keep heli powered till i got home and plug it in? (I use my TX to change Spirit2 parameters on the field via Spektrum integration - which is a great feature btw).
So if you have an idea how i could do it with my setup, i'm all ears (i'm prepared to buy BT module if i need to).

Anyways, flew another 10 flights today, and I have such a blast since updated to fw 3.2.1. It flies just so so unbelievably locked in! Cyclic is another bit better and tail control improved considerably on my heli vs version 2.8. Always had a bit of tail kick on punches no matter how high i set revomix value. Now on 3.2.1 it's gone.

PS: HeliMLM thank you for sugestions and chiming in on the topic, your suggestions make a lot of sense

OK, so just to update on this topic:
Conclusion is, Tomas was right. The rescue inconsistency was caused by excessive vibrations from the motor. It was the pinion that was in really bad shape, and one further crash revealed the solution, since pinion got so distorted that i had to change it, bcs it started to grind against main gear so bad that it was even hard to turn the head by hand. So after installing new pinion the power transition started to feel silky smooth compared to before.
Went for test flying...put it through 20+ flights in last 3 days and whatever manouver I throw at it, rescue will work flawlessly every single time through entire flight.
So this is a conclusion: it was fault of a really bad vibration and not cold weather.
The thing is with this small heli - vibrations from the motor dont get shown on the scale, bcs it only goes up to 500hz. And the Lynx eox 2214 4100kV motor ran on 4s is out of the Spirits vibration scale as it runs up to 65.000 rpm on 100% - which is nearly 1100hz (and I run 70 and 80% which is still 750hz and 850hz and therefore out of Spirits vibration scale)...
Long post but just wanted to clarify that my assumption about rescue in cold weather was wrong and exceasive vibrations was the fault.