Does this sound like a belt issue?
 

New to the Infiniti scene. Coming from a 2002 Audi a6 2.7t v6 TT. Good car, wanted to get something more reliable.

My m35 started making this sound after sitting for 9 hours when it was perfectly fine on the drive that morning.

It makes this sound for about 5-7 miles of driving. Im guessing its belts as the sound reduces with miles and is almost nill after 7 miles.

The oil level is good.

Please state your opinion on what is the cause and what should be replaced.
Also if you can, give an estimate of said repair.
Thanks

Could be a pulley. Is the belt tight?

There is good tension in both of the belts. The belts look alright to me. definitely not like new, but doesnt look like its breaking apart.

Does the sound happen with the ac on or off

Both. It doesnt matter.

Like I mentioned in your other thread. Belt tension is too high or your idler pulley is going bad.

What is a fair price for the idler pulley replacement? Ive gotten a quote for $160 to replace both belts. How much more (roughly) should I expect to add?