I did post already here, maybe someone has an idea.. the RF modulator is knackered perhaps. the first time I switch on it seems ok, but if I reset etc.. it detunes itself and the machine makes a hum like lack of shielding etc.
there is a load humming noise also, I notice it also increase when I have the cassette deck plugged in.
years ago, I remember the same thing when I originally owned an 800xl .. you would start it, and it'd make a noise (like clicking), much like you had your finger down on a key and it was repeating.. maybe the keyboard buffer fills up? although the silver start / option buttons it won't allow me to boot a game off tape.
I'm sure the last bit is a common thing, because years ago I had to get my machine sent off for repair to fix that.
I did get the sams book, as already mentioned but due to remembering the same thing from years ago maybe it's the same fault?
also if I build a scart cable and use that, then it shouldn't matter so much about the RF modulator?
thanks for reading.