Data remanence on CVR
A lot earlier in this thread there is various discussion on the feasibility of the recovery of the [allegedly] deleted data on the Captains flight simulator. The conclusion being that it was trivial is just deleted, but still possible [in certain cases] if overwritten.
In general, a determined enough organisation can recover overwritten digital data from hard-disks and tapes, especially if it is known what has been used to overwrite. Most computer data deletion standards mandate the data is overwritten with random data 5 or more times to be absolutely (spy) safe.
My question is, would the same apply for the CVR? If the duration is 2-3 hours, then the potentially interesting part was only overwritten twice - and perhaps overwritten with silence or a known base level of sound (aiding data recovery). Potentially even if only a few sounds or words recovered could be relevant (to define who was present on deck/a struggle).
Any thought on the feasibility of certain agencies recovering more than 2 hours from the CVR?
Of course, we need to find it first.