Hey guys, I have a weird one for you.
I very recently picked up a 2005 Sport Manual.
With the headlight switch turned off, the Flasher Relay under the dash buzzes like crazy and illuminates the turns signals slightly. The buzzing is very loud, and the turn signals are solid but dim.
If I turn the headlight switch to either the running lights or headlight positions, the noise stops and every thing works like it should. I figured this was an easy one, so I bought an OEM Flasher Relay from Mazda, only to discover that it still does it after replacement. My next culprit would have been the Headlight Switch, so I opened the clamshell and unplugged it, still makes the buzzing noise. I also noticed that the Flasher/Four Ways button does not work, I unplugged it but the buzzing continued, so I plugged it back in.

Here are the ways that I can make it quit:
1. Headlight switch to any position that is NOT off
2. Open a door (only sometimes works)
3. Unplug the Flasher Relay
4. Remove the fuse labeled ROOM
5. Pull the headlight stalk to activate high beams

The car has a touchscreen radio with USB cable routed to the glove box. There are no LED bulbs anywhere that I’ve checked. The stereo plays music clearly and loud, and all of the lights function when I have the switch turned on, including the turn signals.

Any help would be greatly appreciated!