I’ve had similar problems lately. You can try to disable dynamic power management (DRM) in the AMDGPU driver. The following command locks DRM to the high profile (until you reboot).
# generic for AMDGPU, non-distro specific
echo "high" | sudo tee /sys/class/drm/card0/device/power_dpm_force_performance_level
It haven’t eliminated the issues for me, but it did reduce the frequency of the freezes and stuttering.