I get this message when I tried to play a channel with Totem from the web gui.
RTSP: 127.0.0.1: rtsp://127.0.0.1:9981/service/_dev_dvb_adapter0_Conexant_CX24116_CX2411811278000_V_satconf_1_013d -- Unauthorized
A password window showed up and the only passwd I know is my system passwd and the TVheadend passwd (they are the same). I am in the group 'hst'