The federal Eleventh Circuit of Appeals -- which handles appeals from federal courts in Alabama, Florida and Georgia -- has told the Free Law Project that it will soon being posting audio recordings of all oral arguments.
The leaves the Tenth Circuit as the only federal court of appeals not posting such recordings. As I explained in 2014, the other federal appeals courts have posted audio recordings for years. Even the U.S. Supreme Court posts audio of arguments to its website at the end of each week (while releasing transcripts of all cases and audio of a few prominent cases on the same day they are argued).
Among the lower federal courts, many of them post audio recordings on the PACER online docketing system.