Sos valve seal help fast

Every time you float the valves the springs give up a little pressure,I would imagine that they are at the point that they now are taking out your seals.
Spring cups are not really going to solve anything if your valve springs have lost enough pressure that they are bouncing around enough to take out the seals..
If you have a machinest that's looking at your heads...let him do his job..he has the heads, he can see what's really happening. No guessing involved...
My best guess is you killed the valve springs...