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So I recently installed 6 ceiling LED lights with a Lutron dimmer switch in the living room. The power for the lutron switch feeds another switch (non lutron)for an outside lamp just outside the front door.
I just found out that the outside lamp (non-led) would flicker anytime the living room lights are on.

Before this, I thought it could be a faulty bulb, but every bulb I tried did the same thing, though at a different rate. Then I thought it must have been the dawn sensor on the lamp, but replacing the lamp didn’t solve the issue. SO now that I know what causes the issue, how do I fix it? and what is really happening?