For some reason, the AM reception on my radio has gone very poor.  On some channels that I regularly use, there is just a crackly hissing noise, as if the station is "off tune", For example, Radio 5 Live, which I used to get no problem at all on freq 693, is totally unreachable (if that's the word!).  I am able to receive freq 909, which was always worse than 693, just about OK, but only with the volume turned up much louder than normal.  FM is absolutely fine, no problem with that whatsoever, so I don't think its an aerial problem.

Anything I could investigate?

Hi

AM what's that then??

Only kidding, I'm not sure how it works in a modern car stereo, but it use to be that Am and Lw use a internal antenna and Fm use the external antenna, the aerial

Do you get a good reception inside your home, if so it might be a bad connection on the aerial or there's a problem with the aerial booster

My s-type uses  aerials built into the rear screen and then they go through a booster, then to the stereo, if the booster has failed or has a bad connection, it might struggle with am channels,  but be OK with Fm as it's a lot stronger signal

Cheers

Joe

Wow i didn't even know anything was broadcast on AM anymore . Shows how much i know 

Fuse "F43" in the passenger compartmen refers to an "antenna module" - worth a look?

I haven't tried F43 yet.  My AM works until I start the engine.  Then it goes to static like Joe describes.