"loose" sound

My 2001 Boxster has been making this faint noise and I managed to record it.
It sounds like something is loose around the steering column or under/behind the dash.
You can hear the sound from [clyp.it]
It's most noticeable starting at the 20 second mark when I'm coasting to a stop and there's less engine noise.
Any ideas would it could be?
Thanks!

Have you checked under that cowl cover? Could it be something loose with the wiper assembly, battery or even a tool left in that area if some work has been done lately.