I have an 07 SG and approaching 1000 miles... yeah, same whine & noise in mine. The noise "sounds" like a bad clutch basket rocking on the trans shaft and then a loose primary chain...yeah I know,... but thats the best description I can come up with.
I can make mine do it in 5th around 2200-2400 rpm...like lazy shift from 4th to 5th & just cruising along. The 5th gear whine is loud at those rpms but quietens down the faster I go.
I have talked to two Serv Mgrs and a couple Good HD Mechanics ( guys I know personally from my shop days ) and the factory does know about it and is working on something to fix it. One Serv Mgr told me that 75% of all new bikes sold recently have come back in to complain about this same problem. One PHD Mech told me he totally disassembled the owners 07 SE tranny to try to find the cause and even installed different parts but couldnt get rid of it. He did say that he switched the fluid over to Redline Shockproof and it helped the whine some. Most agree that it appears to be a design issue but have no "fix" for it yet.
Tomorrow I do my 1000 miler and it will get M1 V-Twin & Redline Shockproof .. .. figure it cant hurt...
Friday Im off on a weekend long road trip.....maybe it just needs more miles.....
ps: I have a really nice 1998 FLHT For Sale ... nice quiet Transmission too....check web site below
Reno
www.FastAire.com