2005 Mitsubishi Outlander LS, Poor AM Reception

I'm dealing with 2005 Mitsubishi Outlander LS with poor am reception from the stock stereo. FM is alright for the most part, and it does get some AM stations, but other ones are complete static. I tried a different Mitsubishi stereo and an aftermarket swap to test, but there seemed no difference in the quality. And these stations all come in really clear from my car parked right next to the Outlander. The 16" antenna mast is located on the rear roof of the vehicle. I ordered a new one to try out, but is there any other things I can test to determine what the problem is? It has a pink wire to power the antenna. Does that mean there is an amplifier for the antenna? Could that be faulty? Would a AM/FM booster be helpful? I would appreciate any help I can get. Thank you

sounds like a known problem, there is a service bulletin about it- No: TT-119-54-002 DATE: September/October 2005 MODEL: See Below SUBJECT NO AM RADIO RECEPTION No AM Radio Reception - 2003-06 Outlander. If the radio has good FM reception and no AM reception, the AM amplifier in the antenna base may have failed. To restore AM reception, replace the antenna base (p/n 8723A024). 33 years as a installer now just a retired old guy. Favorite thing to install/topic are remote starts/car alarms. Stop using test lights!!!

Thank you for the quick reply! That part number directs me to the antenna mast. I ordered a replacement for that, but it was an "OEM style". Figured I would try $20 before $130. But I will definitely be looking at the antenna base next. I was hoping that the antenna amp would be separate from the base, but if the mast doesn't improve the reception, then I will order the new base and go from there. Thanks again!