That sounds like a potential vibration problem upsetting your attitude solution.
Chris, please watch the new video I uploaded !
its look like there is something not quite well going on in the swash plate when I run different modes !
I think if I fly it as is will crash!
I tried to go back to 3.6.9 but when I install it in the pixhawk the radio setup page and the swash not responding, I tried to use the frame type _class as Heli but nothing moving
on the Qgroundcontrol telling me there are so many parameters missing!
I tried to uninstall the both Qgroundcontrola and the mission planner but no hope!
so I am staying now with the oldest 3.6.7 version as you see it in the video !
please help me with this
Ozzy
Your video doesn’t seem to be working, Ozzy.
What you are expecting from the Autopilot on the bench is impossible. Wait for Chris he will explain to you how it really works.
BTW I got the video going,Chris.
I was able to download the new firmware
3.6.9 and after 4 days of fighting he Pc and he Pixhawk
Every time I was installing it then Pixhawk missing a lot of awash plates parameters
But last night I was about to upgraded to 3.6.9
With no problems and all my radio setup is working and parameters in there !
I heard that the Bench test is not going to give the clue about the system and because it need GPS and real flight to operate
But is there a way to test the flight modes and the system before the first test ???
I don’t want to get a heart stroke 
Thank you
Ozzy
Ozzy, the only valid bench test is in unarmed state in Stabilize or Acro. The system expects different behavior in the other modes, and when armed, that can only be duplicated with a live helicopter ready-to-fly. For instance, in Loiter you do not have collective or cyclic control. The autopilot does. And you can do is make requests to the autopilot to move it or make it go up or down.
The only two manual modes are Stabilize or Acro.
Acro has strange behavior in Copter on a bench test. If you want to fly a greatly improved version of Acro you can load the ArduHeli 3.6.7 build from here->
The information on the new acro in the ArduHeli build can be found here and this has been a very, very popular enhancement for helicopters. There are some outdated links in that thread, but the latest version is in ArduHeli 3.6.7. There are several other features in the ArduHeli build as well, that Copter does not have. But you don’t need to worry about any of that stuff for right now, just to get your heli flying.
I have updated to 3.6.9
Is that the newest one ?
It took me 4 days to fix the missing parameters with that version
Thank you
Ozzy
Ozzy,
The 3.6.9 is the latest build for Copter not for TradHeli. You should follow the link Chris gave you for the latest stable Heli build, its version 3.6.7.
Use QGControl to upload it manually to your Heli.
There is a 3.6.9 build for ArduHeli that has the same heli features as the 3.6.7 with the addition of four-servo swashplate support, but it is based on Copter 3.6.9 instead of Copter 3.6.7.
The difference between the two is the IMU “hotfix” that was put into 3.6.9 for Cubes, and the new “watchdog” that reboots your controller in-flight if the main loop locks up. There is both ChibiOS and NuttX builds for both. And, of course, the ArduHeli 3.6.9 build has support for four-servo swashplates, so some of your params may be missing with 3.6.9 due to different handling of swashplates. There is a description in the release notes that explains what the new swashplate settings are, and what they do for the 3.6.9 build as this was not yet documented in the wiki and it was targeted for the Copter 3.7 release.
so Better to download the 3.6.7 since its free of problems and don’t really need 4 servos!
I installed the Qgroundcontrol in my PC and connected the pixhawk into the SUB
clicked the frimawre then on the right giving me two options;
Ardupilot flight stack
pix4 flight stak v1.9.1 stable release
down there is a chibios and nuttx
and I see only arduheli 3.6.9 I don’t see 3.6.7!
and down select what version of the above flight stack you would like to install
and choices ;
standard version stable
beta testing beta
developer build master
so how to get the 3.6.7 ?
I appreciate your help!
ozzy
If the 3.6.7 build is the one you want, you have to down the proper firmware for your controller from here ->
Then in the firmware install select the Advanced checkbox and install custom firmware file.
Chris, sorry about my so many questions;
I plugged the USB then clicked to choose px4 flight stack V1.9.1 stable release
then advanced setting and choose custom firmware
then hit OK
and the window opened to pick your saved file…
you gave me the link, I opened an I see only in the bottom
assets
and so many links for different devises
now my devise is PX4 FMU V2
that was the Qgroundcontrol telling me in the found devise (frimware window)
so I pick ArduHeli-3.6-Stable-fmuv2.bin
or any others ?
and even if I choose that one and finish downloading it and hear the music tone
still I can see on the summary that the firmware v is 3.6.9 !!
its little hard for me to tell which link need to pick?!
thank you
Ozzy
The firmware will still identify in the summay as 3.6.9 so you don’t get complaints from QGC about running outdated firmware. But in the logs I can identify it as ArduHeli 3.6.7 so if you have a problem I can tell what firmware version you got.
So is the ( Arduheli-3.6-stable-FMUV2.bin ) what I need to click and download ?
And my Pixhawk is the pix4 mfu v2 that what in the frimWare setup page saying !
I think I may have to calibrate and redo all tuning again !
Thank you very much !
I just re installed ArduHeli-3.6-Stable-px4v2.px4 nuttx
but the problem is that I can’t connect my wireless telemetry link to QGC or Mission planner!!
its frustrating! 
Ozzy
Still no hope to connect mavlink to any software!!!
I think it’s the frimware problem
I had no problem connecting mavlink with 3.6.9 before !!
Its look like the 3.6.7 not for wirless mavlink
Ozzy
I’m not sure what the problem is, but the firmware version has nothing to with connecting with MavLink. I run the 3.6.7 version and connect to it with MavLink all the time.
It’s keep telling me time out
And I tried all ports numbers
Also I checked my hardware usb port and it’s same as the qgc and mission planer
I also tried my Samsung tablet but not connecting
I had no problem connecting with the 3.6.9
But this happened after I installed 3.6.7
Do I use the right firmware between all those 3.6.7 versions ?
Thank you
Ozzy
To get a clean Firmware install I would load a Plane Firmware into the Flight controller first and than the Heli FW of your choice again.
problem solved //// problem solved !!!
I spend few days looking to solve the mavlink connection problem!
finally what I did is to Uninstall the driver then restart my PC and everything looks perfect!
I had my very first hover flight today in stabilize mode and its good but its forcing me when I want to move my cyclic sticks… and start swinging back and forth ! and very hard to tilt it left or right!
like a coax heli!
maybe that is the tuning job
but I have a message says ; parameters are missing from frimware. you may be running a version of frimware QGC does not working correctly with or your frimare ha s a bug in it.
missing parameters : 1- AUTOTUNE_AXES
dose that mean I need to redo all the frimware flashing and the reinstalling?
Thank you
Ozzy