[ICOM] Cleaning up faceplate knobs

[John Geiger]

I have an Icom 706 original I picked up a couple of months ago. Yesterday
while taking it mobile I realized how dirty the knobs are on it.  Usually it
sits in the semi-dark shack and I don't notice such things.  There is some
sort of hardened gunk in the grooves on the volume and RIT knobs. Not the
end of the world but would like to clean it up, if possible.  What is the
best cleaner to use on plastic knobs such as this?'

73s John AA5JG