Strange power fluctuations LimeSDR-mini

Anybody have mentioned tha same bahavior?
Is it SDRangel defined, or internal hardware issue?

I have found the strange behavior of output power of LimeSDR-mini. The power is set to maximum in Sdrangel. I use 20 dB attenuator, cause my power meter accepts levels up to 0 dBm. As it seen froõ video the power level goes from the maximum 15 dBm to 6 dBm and the back to 15 dBm. And then repeats again.