Issues with FM radio after audio jack and charging port board replacem

I've recently repaired my partners fathers phone, it suffered typically from a dodgy charging port and audio jack (he's a gardener and his phones take some abuse) after a plethora of problems arising from this I've finally nailed down all the issues besides one.

The FM radio won't work on the phone , it gives static and crackles both when through headphones and when set to speaker with headphones attached as an antenna, I've fully updated the software, cleared the cache and data, even put the old jack and charger board back in to see if it was a hardware issue with the replacement part but nothing seems to fix the issue. The only thing I haven't done is hard reset the phone due to the hassle of it for her dad, all the antenna cables are intact and I've also replaced the mid frame with all the antennas to be sure of this. Does anyone have any knowledge around this? Even just a list of the required components to make it work so I can troubleshoot myself through trial and error would be massively helpful. Thanks!