I have fantastic news!
After much effort on his part, Amizaur has sent me a combined complete reworking of both the Sound vs. Speed fix and the submarine passive sound levels!!!
New SSN's will have a different speed curve from old SSN's. Submarines that are realistically quiet when still but very noisy when moving, such as older SSK's, will be modelled as such at realistic sound levels. SSBN's will be relatively quiet at max speed, and the quietest SSK's will be wery wery quiet...
There is still some work I have do in integrating it into the working database, but we have something very good coming for you here!
Cheers,
David