[Welsh Anorak]

I have a late 1400 which suffered from frame linearity problems. After replacing various capacitors I was rewarded with frame collapse. I had replaced the 1uF capacitor in the boost/height line with a new part and the set didn't like it. Only when I put the original back did it work. My manual shows this part as 0.1uF but was changed for late production. Any idea why a new capacitor won't work here? I tried two of different makes and no joy. Odd.