First of all, do you mean NEVER heard the station, or USUALLY do not hear the station?
I'd have to think about the Straits Area, and never vs. usually, but at the regular Southeast Michigan location, definitely WFLT 1420 Flint (Legacy WAMM, where Casey Kasem did his first Top 40 gig, according to Casey himself, in 1957!). It is 41.77 miles away from my RL according to AM Query.
At that RL, WHK 1420 Cleveland comes in almost exclusively. Every once in a while, WFLT runs on STA nondirectional at 125 watts, and you will hear it a little in the background. If you go to a Cider Mill just 10 miles to the Northwest, WFLT comes in quite well, without almost any interference from WHK. This is due do the WFLT Directional Antenna, and a particularly bad patch of conductivity to the Northwest, which is much less than M-3, which nobody believes in but me. But it manifests itself as gravelly, stony, rocky soil, from glacier deposits, poor conductivity for all AM signals in that direction, and prevented the Clinton-Kalamazoo Canal from being completed when it reached Rochester, MI. The project was abandoned in 1843. They ran out of money when the soil went quickly from clay silt to rocky in about 12 miles from the start in Mt. Clemens. The carved out canal valley remains, marked by a road named Canal Road. So that bad patch has been there for a while. You can also see it manifested on the original WUFL 1030 Sterling Heights original DA Proof of Performance maps, where it resulted in a massive dent in the contours right in the major lobe of the DA.