Have you had the windshield replaced?

Cracking noises can be any plastic pieces touching the glass as the two surfaces heat and expand at different rates. Can happen after glass replacement or not; sometimes some padding at the edge of the glass can help.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue