Agree it could be the switch. Without a relay, lots of current goes through the switch so even a little extra resistance causes a problem. Much the same as for power windows.
I am fighting with a bad hydraulic top cylinder right now too. Doesn’t take much of a leak to make those operate erratically. Wondering if I might be able to rebuild original cylinders as Royce suggested. Didn’t want to hijack this thread, so started another on that topic: