I had this problem last year, twice. First, I put the car into yearly maintenance and they told me the hoses were leaking and they replaced it. And second time, I took it in for a software update and they told me it was leaking again. So they replaced it and they told me if it keeps on leaking that they had to replace the tranny. Because, they figure that it wasn't just the hose it was the screw thread on the tranny its self.
Hope yours get settled soon.
e90 m3 melbourne red metallic, "One and Only" e90 sedan Amuse Ericsson full exhaust(new model)with custom spec, Afe intake with stock box,piano black trim, blackline tail, HRE P40 9x19,10.5x19