BMW: noise coming from the gear box, loud sound, transmission fluid

Question
Hi Josh i have 89 525i when i start the car i hear that loud noise i dont know exactly from where comming i hear it near to the shaft stick but when i move to D or R it become not loud sound  it sound like (Ezzzzzzzzzz) and my RPM runs high run like 1200 cold and after it wormed up gose down but when i drive it like 25 miles and put it on P it gose up again to 1200

thank you very much for your help  

Answer
 Ash,
 I need you to be more specific in what you are asking.  

 Have you checked the transmission fluid level?  Have you had the transmission fluid changed lately?  It could probably use a new filter, and transmission fluid.

 Try this first, then come back and see me

 Thanks,
 Josh