My mates MKIV Golf has been doing this for well over a year now without any issue, just a quirky noise frmo the starter motor when starting the car, but always starts each time, his car is just a cheap runabout so he doesnt really care to look in to it so for a resolution, i dont know, nor do i know if its doing more harm than good by carrying on as it is.
Sounds like a deranged Cockrel or something is the only way i can describe it