Paul, the reason 5 isn't tuning is still a mystery. I swapped all the chips. No result. However the reading I was getting... that was on the wrong resistor. They changed the pattern I see. The envelope is showing up if I get it on the right resistor :-). It looked like a clear pattern but for some reason on 5 they changed it! I couldn't see the writing... anyway I figured probably the hard wired leg 4053 chip but no dice. Still doesn't tune until I turn it on..then..I find out ..it's tuned. Whaaaaatever. I dunno. I need to see the code i guess to know what routine it goes through on the tuning. lol