Land Rover Repair: wierd noise, noise question, electrnic

Question
QUESTION: I have just purchased a 2006 4.6 HSE Range rover
At 71mph a high pitched "ringing" noise can be heard.Its like a faint electrnic alarm clock sound. It is only at 71 and I cant tell where its coming from - sound like towards the back but even two passengers listening in back couldnt determine where it was coming from. Everything works well no other known problems- any ideas its driving me nuts!

ANSWER: It's possible you are hearing a resonance from the driveshaft.  Noises like that can be very time consuming to nail down.  You may be in for quite a few hours of diagnostic time to hunt that down.  There is no "common cause" for that problem

---------- FOLLOW-UP ----------

QUESTION: thanks, sorry to bother you again but is it fixable? If driveshaft how do they deal with it

Answer
We have spent 5-6 hours hunting noises like that in my service department.  Pursuit of that noise could have a significant cost to you if the problem is not obvious.  So I'd suggest you prepare yourself for that possibility if you want to go down that road.