Dct transmissions wine noise

[m5dream]

Hello everyone 2016 m5 58,000 miles.
The CT fluid was changed last year at the dealership. I recently purchased a car three weeks ago. I noticed under regular slow acceleration, once the car gets to about 30 mph and hits fourth gear a louder pronounce sound can be heard. Sounds to me like it Hass to be coming from the transmission. I will attach a sound clip. It starts right around the 10 second mark when it hits fourth gear you could hear a audible louder sound coming from what sounds like the transmission. The sound lasts for about 5 to 6 seconds and seems to go away as the transmission kit keeps shifting into upper gears. Any ideas guys let me know


https://youtube.com/shorts/C4Jnt1t69cA?feature=share

[M5Rick]

Could be the diff as it's a constant feint whine. The oil in these needs changing every 25k miles depending on how hard the car is driven.

[m5dream]

Originally Posted by M5Rick

Could be the diff as it's a constant feint whine. The oil in these needs changing every 25k miles depending on how hard the car is driven.

I don’t think it’s the diff cuz if it was the diff it would be constant and get louder with speed it doesn’t.
It’s specific to speed 35 mph I start to hear it and 40 mph it’s more less gone


But I will be changing rear diff fluid soon