Ah, nice!
The best remedy for that would be to replace the 125K resistors with grid chokes (preferably from Magnequest).
What you'll want to look at is the voltage present across the 125K resistor. If you have the + probe on the grid, and the - probe at the negative rail, you will probably read some negative voltage across the resistor. Where things get nasty is if this voltage wanders around with signal or time, but the low DC resistance of a grid choke will solve that problem nicely.
-PB