Whistle kind of noise

Car shifting fine

Check for vacuum leaks.

Wouldn't the noise come if the car is in park if it's a vacuum leak?

Driving creates more air flow through the engine. Just a guess with little to go on.

It gets louder when car is engine braking

May be within "normal" range for the CVT "whine/groan/moan" continuum, as they're louder in the harder working 2.0 Imps than the 2.5 Leg/OBs. If progressively getting worse you'll need a new CVT, as it probably has a worn internal bearing. Change its CVT fluid ($100) first, if you haven't yet. Any CVT synth is ok.

So took it to the dealer thought fluid change will make it a bit quite they ending up telling me It won't and will need to replace the trany. And the reason thy told me was because thrs a "band"inside the tranny which will go bad if drive continuesly everyday for same amount of miles. Which i do drive on the highway 100 miles everyday. So they told me its out of warranty and i have to pay $7500 out of my pocket. So i got home and called the subaru corporate office and threatened to sue them and they ending up putting brand new tranny. They should really but a recall on them cvts since dealers cant even fix the transmission. These cvts will go bad after 100k miles. What a shame !!

Thanks for sharing. Since most 100k+ CVTs run just fine, it's not clear that failures are correlated with use or bearing failure. It's just too idiosyncratic right now....

That is a new one. Transmissions that fail because of commuting the same distance every day.

I have a 2014 subaru impreza 2.0 with 41k. I have the same whining/whistle noise issue. Is this a serious issue?Should I be replacing the cvt fluid?

To check if its the same problem. Put the car in neutral while driving and see if the noice continues, if it does its nothing to do with cvt but if the noise goes away that means it is your cvt. Now i had this issue and i took it to the dealer. They told me i will need a new tranny since thrs noway to rebuild the cvt and changing fluid wont solve the issue. So i called corporate Subaru and they got my transmission replaced for 0$. And 2 months later after i sold the car, I received mail about the recall notice for cvt transmission. So i would definitely take it to the dealer and have them replaced the cvt transmission. If you need more help let me know i can dig out the recall mail that subaru sent me.