Just started noticing a whistle noise in the cab. It sounds like it is coming from the center front firewall area, this does not change with throttle response but with speed and is not there all the time. I have noticed it at about 65-75 mph with or without a headwind. We are checking the windshield but have found nothing yet. Anyone have this problem.

2004.5 LLY ALLY ,PREDATOR ,AMSOIL