The cache is not purged

Manimal_

I was investigating on my sound issue with localized voices and noticed the cache was not purged after FAF updates.

So many FAF obsolete versions are remaining stored there for nothing.

Take a look at AppData\Local\Gas Powered Games\Supreme Commander Forged Alliance\cache

BTW :
I'm wondering how to run FA with the /purgecache command line switch through FAF.

Nex

This is probably intentional, as you need the old versions to watch older replays
So once a player watches an older replay, the client keeps that version around in case the player wants to watch another one of those replays

Brutus5000

That cache is a game cache and not a FAF client cache.
If you want to apply the command switch you can append it in Settings -> Forged Alliance Forever -> Command Line Format for Executable
Put it behind the %s

(Mine might look different because I'm running on Linux)