Dallaslebeau21

I have 02 6cyl 2wd trailblazer. I few days ago my blinker on the drivers side started acting up. It works fine when normal driving but when pushing brake it blinks fast like its out. Checked all bulbs and are fine. Even.switched the bulbs from passenger to drivers side and same issue. I also noticed when I put in reverse it does it amd also dims more. I checked the bulbs I checked the ground, im at a loss I dont know what else it could be. Any hints advice is greatly appreciated in advanve.