USB3 Oscilloscope (slow) - CPU core burst to overflown memory in oscilloscope


I have USB3 oscilloscope and according lsusb -t it is superspeed (5000M). When I run it in streaming mode at approx. 6 MS/s, the reading rate leads to overflow event in several seconds and htop shows me single core 100% loaded. What it can mean? Could it be wrong drivers, or is it natural behaviour of the SBC (Odroid XU4).

Thank you…