Not to be a guy who responds with an immediatley negative comment, and then post what may be an unreasonable solution but my thoughts..
Stock headlight is garbage, and useless. Had mine for 3 years, but never rode at night, this summer I started too, and realized it for the hazard it was. Too easy to get over your head with a light that's only good for 40 kms per hour or so...
I went through 2 bulbs myself, and rather quickly although I just wrote it off as poor judgement by KTM by putting a bulb and system in the bike that is not "quality", and is there strictly for show.
That's the negative..
For my was the Lynx kit from Britannia Composites. Great (awesome) lighting and a functional, adjustable windscreen all in one. It costs money, but allows you to ride at night with confidence, to see better, and to be seen better as well by oncoming.
My opinion is forget the stock light, I'm not "hardcore" by any stretch of the imagination, but the stock light agreeably cannot be used for evening riding, to dim, hard to make out hazards on the flattest of surfaces.
Big Money to spend on the 690 to purchase for most, including me which was why I sat in denial so long and did multiple 2500 km trips with a stock 690. Don't wait like me, look for improved, reliable lighting (Lynx is my vote for value, service, look, fit and finish!) But there are other options. Money well spent, and will open you up to many more riding opportunities!
Even pavement riding will kill the filament in the bulbs used in the stock housing, let alone the shake rattle and roll of even the mildest offroad methinks.
Of course, this is advice from the guy who still hasn't chased down his own gremlin with the stalling, but snow and an unheated garage has dimmed my interest and my wits of late