newsletter: Add a section on audio support

src/content/newsletters/2024-09-30.mdx

@@ -64,6 +64,12 @@ At the time of writing we are passing 588,982 more subtests than last month brin
 
 Our current WPT progress can be seen [at wpt.fyi](https://wpt.fyi/results/?product=ladybird).
 
+### Audio support
+
+We have been replacing our home-grown audio codecs with FFmpeg's excellent libavformat and
+libavcodec, which means that we now support a wide range of audio formats out there on the web!
+Vorbis, MP3, FLAC, Opus, Wave and many more can now be heard in Ladybird.
+
 ### Credits
 
 We thank the following people who contributed code to Ladybird in September 2024: