My blu-ray player on my

i`m pressuming you are in the uk ? if so !

Go to acer arcade deluxe
select "Play Movie"
Select "settings"
select "BD settings"
Select "region code"
Select "region B" for the UK

Important Note!:
You can only change your region !!! 5 !!!! times!
that is 5 times!
I am totally stressing this.....5 times!

You may have to do this a second time so your computer locks on to this region code.
If you watch an american blu-ray vid, on the fifth change of the region code your computer locks to this region !FOREVER!

have you changed regions 5 times?
it is one of 3 things 1] a defective dvd reader 2] a bad ribbon
3]a ide controller issue unless you have sata dvd rom check for specific drivers for the dvd make sure you have any special drivers if needed I doubt you do though
take the dvd reader and run it as a slave off the hdd ribbon if that fixes it replace the ribbon if not
take the reader back for a replacement