well too both of you
this is easy way to find out if software on pc is causing the problem ..take out the drive and put it in another machine .... and if it works fine then you know it is something software wise on your all pc ...
I have seen this happen if you have clonecd on your machine and have hide atip checked ...anydvd running ... alcohol hide atip media going ...under emulation ...
but that is what I would do .. I am a technician myself I would take the easy route ...and taking out and putting in different machine would be the easiest .//
and you all did update firmware I think but not sure if both ..
keep us informed ..if you need anything else look at signature