Just tested and ServeStream can open .pls files to play online radio (looks like DeadBeeF Player and Stream Furious can as well.. When you click on the .pls link it should be an option to open with after it is installed.
Opening a web-linked .pls:
Then ServeStream opens the .pls file:
Since .pls is just a playlist file with the location to the real audio files you could try to convert it to other playlist files and see if you can open them. Examples are .asx and .m3u.
If you open the .pls file with a text editor, you should be able to see the location to the sound url(s). If it is a single url, you could try to copy/paste that one into a ...
TuneIn Radio has channels for BBC radio, other radio streaming apps probably have them too. TuneIn is a good app, the pro version even lets you record. I am not sure what other features the pro has over the lite version, but I use TuneIn daily.
Hoping that it's the same radio station and I didn't took a wrong stream URL...
AAC Stream: http://icecastsource2.amri.ca/cjab-aac
MP3 Stream: http://icecastsource2.amri.ca/cjab-mp3
I tested this in VLC and it worked.
M3U files store playlists. The M3U files you are trying to run just has a list of URLs to the radio stations. You can only play M3U files on your Media Player if the player supports playing them.
Try the Live365 app. It works great for me. Huge range of stations, both free and paid.