Clutch noise GTV

[Robertor@xxxxxxx]

Hello all, 
I drive a '72 GTV 2000 and I have problem. When I drive the car I hear a
weird, annoing noise, sounds like.....a cable grinding as it turns.. or
something like that. However when I push the clutch down to shift gear, or
stop, the noise stops! The noise seems to be louder if I go slow (either that
or when I go faster the beautiful Alfa engine noise blocks it). Has this
happened to anyone? 
Thank's !!
Roberto
RobertoR@domain.elided

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