I have the same problem, but don't have a streaming client. I also found out, that's a long existing problem (see here: https://www.swtor.com/community/showthread.php?t=985595 and also in threads since 2015) I have installed SWTOR on three different PCs with different graphics and different RAM but on every one of them the same problem concerning the legacy menu. But never found help which actually works on my PCs. I'm nearly desperate.