im using 5.0.375.125. doesnt mention anything about beta. maybe thats the reason?

I'm also using 5.0.375.125 with no issues. I was using a mates Laptop the other night with Internet Explorer, now that has issues!! Kept Crashing, glitches loading etc etc etc.
Firefox is ok but I had a few issues with it and switched over to Chrome, works better for me.