agree Ranger...very hard to diagnose. Sounded like a creaky headset or fork actually. Was the Brooks saddle. Put a different saddle on the bike and drove it for a fair distance and dead quiet...just the melodic whir of a nice Campy driveline...ahhh.
Removed the saddle and was able to recreate the noise of the saddle in my hands.
It comes from the attachment flange and rivets to the relatively hard leather. Lubricating the rivets and brackets is a slippery slope forgive the pun as oil is known to reduce the strength of the leather and didn't want any rivet button holing issues. Many have reported their Brooks to squeak on occassion...the cow may still be alive...lol. Silicone spray does help quite a bit. Was wondering what others did.
Thanks,
George