Tube Whine noise...Please Help

Linkloping. Much like the 6dj8/6922 family of dual triodes ,the 5687 tends to be very prone to microphonics as well. But certainly not all of them, I concurr with your preference to the sound of the tung sol 5687 as it's far and away the best of it's type, particularly the earlier d getter version. That said: out of 11 examples in my stash,I have 4 that are dead quiet and with zero microphonics..... Speedracer,the same can be said for the 6922/6dj8 family when employed in many preamp circuits, and in many cases you need to cherry pick the quiet ones from a bunch of them. When one's preference is for using nos tubes... it can turn out to be a rather expensive crapshoot to be sure. If you "are" contemplating retubing with nos tubes,your odds of success will be far greater by substituting the 6dj8/6922/e88cc for the uprated seimen 188cc or the telefunken 188cc.These tubes, as well as the dutch amperex 7308 are the best sounding of the nos 6dj8 family next to the hideously expensive cca ,they are true low noise 10,000 hour tubes and should last longer than both you and your preamp.They do tend to be pricey though... Another economical alternative is the original nos soviet miltary 6heb or 6hev dual triodes. These are the quietest 6922 types on the planet. They are very linear tubes and have the tightest matched triode sections to boot . Not to be mistaken with the nasty sounding sovtek 6922's currently marketed to the West. These tubes are really well balanced top to bottom,very smooth with great bass punch and a vivid sounding top end void of the glare you hear with the Sovteks. Well worth searching for and typically priced within $10.00 of the Sovteks. Cheers and have a very Merry Christmas and all the best in the New Year.

Amen Boa2!