problem with some ptp

Hi,
I have some ptp that have some problems.
I use 433AH or 411AH with ubiquiti XR5 radio and Jirous 24Db antennas.
The signal is very good (about -50,-60) and 80/90/100% ccq.
Sometimes the link is going down and I can see the log that write: extensive data loss.

Why?? I wrong sometimes in configuration?
I think that is a frequency problem but I try to change it but the problem still is.