So should have said this a while ago ..... setup logs (in menu/setup/) to record to usb or hdd (not flash).
Enable debug logs.
Assuming there is no crash log?, then when it „freezes“. Use putty to log in (ip address, root) enter init 4, wait 20 secs and then init 6 to restart.
Post the log here (debug or crash) ... you can ftp the log to your PC from the usb or hdd.