Jetta car alarm randomly going off

I have two questions related to my '05 VW Jetta GLI:

1) Out of nowhere this week, while parked overnight my windshield cracked. This is the second time the windshield has cracked for no apparent reason, and in virtually the same spot. The first time it happened while traveling through Missouri, the second time traveling in Illinois. The crack started a few days ago and has continued to grow, again overnight or while parked. Is there something that could be causing it to crack and continue to crack?

2) Tonight when locking the car, the lock “beep” didn’t go off. We thought it was weird, but thought nothing of it because the lights still flashed and the locks clearly went down. A few hours later, we heard the car alarm going off outside while parked with no one around (I’m in a rural area, not a city). We went out to check it out, relocked the car, and then had to reopen it to manually shut off the interior lights that had illuminated from the alarm. We locked it again and went in. About 10 minutes ago it started going off again, but then stopped beeping by itself. Is there something that could be causing the alarm to trigger? Is there a way to prevent it from happening?

I love my VW but I’m getting increasingly frustrated with its quirks. I’ve already had electrical issues with the check engine light and coolant light. I’m going to be peeved if I have to take it in for the alarm system now too.

Any tips, thoughts on cause, and future prevention is much appreciated!

If the crack starts at the edge of windshield(twice) it usually means there is a burr or piece of metal in the windshield frame that is putting undue stress causing it to crack. They are designed to seat as expected on a relatively smooth surface.

Unfortunately electrical issues are a more common problem with VW. Usually alarm issues are due to locking mechanism (part of alarm system too) not functioning properly in the previous generation (99-2004 VW Jetta/Golf).