I would assume that for your first paragraph, the power transfer (from APU to generator 1 or 2) can cause the system to reinitialize. That happens a lot, especially with "commercial" systems, such as IFE.
The reinitialization process will do what it says, ie reinitialize and reset everything.
Audio reproducer (tapes, CDs, EEPROMs) therefore can not restart where they stopped, since they go back to zero.
With regards to the PTV, I would think that this was due to a problem, because if it was working prior to departure, it should have been smooth and carry on, apart from thea pause during the safety video/announcement broadcasts.
Shame for the Airshow, but that all depends on the system, and on the customisation the Arilne is asking for, you can either complain to the airline or to the IFE vendor in that case.
For channel selection, it's fairly easy for CD
, tapes, EEPROMS, you just put customised media (CD with only rock for example) and distribute the channels over the seats. IFE softwares are quite amazing and quite complex.
With the server systems, they indeed use MP3, and they simply put them in "genre" folders, and distribute the channels once again. Being digitalized, you can pause and restart whenever you want.
After the button is pressed the screens could automatically appear and the safety video would start. Then at the end it would show airshow and then depoly for takeoff.
That's already like this, at least for some operators.
Automatic and pre-recorded announcements must be like 15 years old or more, so I can't believe an airline wouldn't have them, although they are not compulsory. I believe QTR has at least 6 or 7 different languages on their fleet.
I do not know that Airlines required to shut down the IFE prior to take-off and departure, apart for maybe a very short time-frame (electrical loads issue).
I dealt with a QFA story where they complained about the fact that when the landing gear was down & locked, the audio medias would stop (IFE software deviation), so this implies that they indeed want the IFE to operate until the very last minute.
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