Turn Signal Problems

[sanford66]

I'm having some weird problems with the turn signals on my 72 Custom deluxe. When the headlights are ON the front park lights won't flash with the turn signals at all but the side marker lights will flash. When the headlights are OFF all the front turn signals work fine, same story for both sides. Also the rear side marker lights won't flash with the turn signals at all, with or without the headlights being on. I noticed to that the signals flash faster when the headlights are OFF and slower when they are ON. This has got me stumped! I have spent about 4 hours so far checking bulbs, sockets, wiring, grounds, etc. etc.. I'm not coming up with much, wondering if maybe anyone could point me in the right direction? Thanks guys. Joseph