2005 gti acting weird on crank

So the other day I had stopped to
grab a drink at the store went back
to my car to find that it wouldn't
start. First time the epc(this doesn't
stay on, just that once) light came on
and all my interior lights came on but
turning did nothing. Now it's 100%
random. Some days it starts perfect
sometimes it takes 10 try's to start.
When it doesn't start my clock and
trip mileage reset/ flicker like crazy
and sometimes you hear a loud
vacuum like sound when trying to
start. Have only had it stall on me
one. As in driving and came to a stop
and the power went out in car and
had to turn the keys to get it to crank
again. Any ideas would be very
helpful. 2005 vw gti 1.8t