

That fault is common in vintage stereo amplifiers too. A popular mod is to install a triac so that the switch becomes basically a soft-switch toggling a few hundred milliamperes, rather than the full current draw for less arcing. See https://audiokarma.org/forums/index.php?threads/is-your-unobtainium-power-switch-worth-5-and-an-hour-or-so-of-your-time.504673/ for discussion; not sure if it can be directly applied here.
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