Sound like the low end might be lean so richening up the high end compensated for it but when you lean the high end up it leans out and the running will sag then die if I'm right, try to richen the low end up first 1/8 turn at a time then try setting the top end and keep richening up the low end until you get the rich end leaned out to good running rpm's This is my guess on this one.

Dauntae