One thing I can say about this forum - it will never be serious
Oh HV spike is what initally fires the bulb as said already its around 20,000v
once running they operate at around 85v. I wouldnt spend anything until you have had it fixed though - if it is the bulb it will probably be cheaper than the driver that will most probably cost alot of dosh. If it is the bulb you have to then ask was it being driven to hard and perhaps the new bulb will only have a short life too so driver fault - or perhaps they have just been used alot and really are on their way out... this shouldnt happen untill after 2000 hours or so