Have you tried the following:
"So here it is tried and tested for anyone who is trying to roll back from 3.01 to 3.0.
This keeps the other 3.01 settings and only rolls back the 1.3 Flight controller included in 3.01 to FC to the FC 1.29 included in the 3.0 update, and thereby removing the 119m height restriction.
This is updating via the GUI and slightly different from updating from other settings via the GUI, so follow the steps exactly. (The power button on the H is never touched in the whole process - the H remains off, the USB supplies power directly to the FC board).
1. Download the 1.29 flight controller from here
Dropbox - TyphoonH_FC_V1.29_21_10_2016.yuneec
2. With the H powered off - connect the short supplied USB to the bottom of the H body - do not connect the USB to the PC yet!
3. Launch the GUI
4. In the GUI go to Tools>Firmware Update
5. Select the downloaded 1.29 Flight controller from step 1.
6. Plug the USB into the PC - (Do not power on the H - The USB cable provides power directly to the Flight control board, the H will not light up).
7. As soon as the GUI see's the H it will load the 1.29 Flight controller.- Wait until the progress bar is finished and you will get a Firmware success message - Click Yes.
8. Unplug the USB and Reboot the H.
9. Calibrate the compass and accelerometer.
That's it...I've just tested and flown above 119m I still have the dual redundancy wifi and other features of the 3.01 showing on the ST16."
I did this exactly to the tee and got GREAT results. I haven't had not one single problem with my H. I've gotten up to 850ft... (i did this to get farther down range). I was at a park that time with trees towering well above 50ft. LOS was horrendous (i'm talking i lost LOS at 900ft away because of the trees)... but the drone flew 2300ft perfectly without video loss and telemetry (this was on a stock antenna).
I've heard great things about the new FPVLR antenna's (plus boosters). Carolindronez also sells the 2.4ghz antenna upgrades that goes directly on the H. I'm going to post that soon.
Reason for the height change needs is that the only way to get a telemetry and video to stick is to get the drone higher... unless your LOS is great due to a very wide open space (talking pastures here, LOL).
Anyway, try the steps above... no bugs AT ALL! I've flown MANY MANY MANY times flawlessly.