Left turn signal issue.

Okay so heres whats going on with my 68 plymouth Valiant. When the left signal is on it stays solid so no intermittent signal. (last year I had to soder the front turn signal housing because it had a bad ground from the socket to the housing) Both front and rear light are bright so no burned out bulbs (all lights on the car are new). The right signal work correctly. All 4 lights flash when the hazzards are on. I was told its in the switch and not the flasher relay so I was hoping to get a second opinion before I order a new switch.