hissing in the AC

[JeepDxb]

i go for night drives to the desert taking my commander 1999 as it is winters and my wife loves these drives.

recently i have noticed a very low hissing noise coming from the AC duct (which we don't switch on) apart from the noise my ac is fine even in the afternoon. should i be worried coz this only happens in the desert

[JeepDxb]

close ur outside vent, it may be coz of that. if not dont bother there are things slight noises and pinking u hear desert from ur car as its QUIET place. But if no problem then dont bother.