Solved by searching dmesg log and matching errors from here: "PCIe Bus Error: severity=Corrected" on Jetson Nano - #3 by vidyas
added pcie_aspm=off to extlinux.conf kernel command line :)
I will rebuild kernel with more permenant settings:
Removing “CONFIG_PCIEASPM_POWERSAVE=y” and setting “CONFIG_PCIEASPM_PERFORMANCE=y” in the kernel configuration```