Is this the signs of an electrical problem??

[78-300cd]

Hello,

I have a 1978 300-cd. I was driving last week and while stopped at a red light a hairline tail of smoke came out from under where the horn is on the steering wheel. I immediataly associated the smell with that of electronics. It stopped after like 10 seconds but the smell lasted. All the electronic switches work, after i tested them after. Then a week later the smell came back strong again, this time i heard some weird clicking to the right of the radio. And agian everything works fine.

Any suggestions?