Eduardo, I am using those exact radios on a rotorcraft with the same results you have. What I have found is that the telemetry going down the link from the aircraft to the groundstation was at such a high rate for 9600 baud it was consuming all of the available timing for transmission. I tried quite a few settings in the software to try to get them to play correctly, but in the end I went in and adjusted the frequencies of the telemetry.xml file. Even doubling a couple of them, and making sure to offset the values some can make a world of difference. What I mean by offsetting is if you want a couple things at 1hz, you will run into less of an issue if you put 1 at 0.9, 1 at 1.0 and 1 at 1.1 vs say puting them all at 1.0. Give it a try, it certainly worked for me.