Weird sound from behind dashboard

hello, 3 months ago i bought a SH audi a4 b5 , great car, no problems, with a 1,6i engine just enough for me...

a few days ago something happened, when i start the car (AC off, radio OFF) after 10 sec of idle a strange hissing sound starts from behind the 3 air outlets in the middle of the dashboard...i have no ideea whats causing them, and its soo anoying. It dosnt get louder if i accelerate, if i use AC or if i use the radio etc. , its just there ... i start the car and its all soo quiet for 10 sec then it slowly starts in a 2 sec interval . .. . liek something kicks into play after that time . is it from the AC sistem ? the ac works great, cold or hot air anytime anywhere... i cant hear the sound from outside, or maybe it is but the engine blocks it ... inside its driving me crazy ... any suggestions or if any1 had this before PLEEASE help me out , i just love this car but that sound is soo annoying .

Sounds like when your staying near high voltage cables ... and i can hear something like rotating inside there ... but not sure.

thank you, hope some1 can help me out.

Audi a4 b5
berline
1,6i

Perhaps a cable is damaged or the controller for the ventilator is stuck on max.

I had a similar problem once, the sound started being very loud, then around 30 minutes later when the engine was heated up it disappeared. It really sounds like a damaged cable to me. If you find your solution, make sure to let us know!

well i just took a little more time to figure out whats going on and i realisez the sound is coming from right behind the AC control unit, under the radio/cassete . is there a fan or some sort behind it?If i knew how to get the radio or the AC unit out i bet i could see the noisy thing ... Do i have to remove the whole dashboard to remove anything from there? any1 got any clue on how to get there?

I figure its a cooler or fan of sort because when i stop the car its slowly stops rotating just like a PC fan loosing power.