could be either or both still, having the software issue for long periods can damage the battery, also remember the mmi meter is crap, not accurate at all and gets its info from the very module that has the software faullt in the first place.
also there are varying degrees of this issue, the most common is the battery remaining at 10% (but can go up and down ) - but the battery doesnt discharge its a false warning from the module which then causes other modules to shut down as it believes theres not much power. then theres the other end of the scale where the battery needs replacing as well (according to the Audi TSB).
if you have checked the state of the battery with a multimeter and it reads ok, turn on the mmi without the engine on. if you get the "3 minute warning to shut down" within 5 minutes or so its likely the software is at fault.
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A8 4.2TDI - Ice Silver, Comfort heated/cooled/massage Seats, Alcantara, Extended Leather pack, Ambient light pack, Solar roof, Night Vision, Lane change assist, Audi presense, Audi BrakeGuard, ACC Cruise, Blinds, Quad Air, AMI, Online services, Parking with rear Camera, Aluminium brushed inlays, Adaptive Zenons, High beam assist, Bose Sound, and more
Gone but not forgotten: A8 D3 2005- AMI HDD, Audible Parking, TV, NAV, Bluetooth, Hybrid TV, Aftermarket headrest monitors, Rosstech VCDS / Vagcom
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