No More TT Feedback

I consider myself a fairly intelligent guy. I've been thinking my TT feedback problem was related to support vibration. If you have been following this saga, you will know I've tried spikes,foam, even built a separate platform (I needed that anyway) for my TT accessories and the TT itself. I was having a couple "Dos Equis" and I got this idea to add weight to the TT. As the record was playing, I carefully put down a cloth on my dustcover (I hear the high end tables do not have dustcovers) and put aprox 5 lbs of dead weight on top. BINGO! My vibration problem was non-existent. My dustcover is hinged in the back and the front corners were not completely touching the TT base. Therefore the dustcover and would build-up harmonic vibrations eventually being picked-up by the tonearm. Even with the cover open, it would still vibrate, so I never associated the cover with my problem. As soon as I added the weight, it made the dust cover touch and no more vibration/feedback. I tell you this running the risk of coming off as a fool, because I didn't want anyone else to make the same mistake.