Programs lock up after a number of minutes

I bought my WD media streamer a few weeks ago. It worked fine until I received a message asking me to update. Aftyer it downloaded and rebooted, when I try to run a program ( say view a video etc ) after around five minutes the system locks and you cannot even turn it off without disconnecting the power. Can anyone suggest a solution please.

Maybe a full factory reset might help.

Thank you. I will try that