I took apart an old SkyHD decoder about a year ago and tried connecting the Hard Drive to my PC.  I couldn't read any files, but downloaded some software called ExPVR to decode the files - this worked and I could view the contents, but it was tricky to use and I am always a bit suspicious of free software. Once you know the file type (and possibly the make of the innards if not B&O), you may be able to find similar software for decoding purposes.