[mythtvnz] Prime has no PMT

[noel at igrin.co.nz]

I am using DVB-S and when changing channel to Prime, I get L_S being
reported.
Which I gather means Lock achieved on a Sat Digital transmission, but no
MPG stream found. I can get Prime FTA on a standard Sat receiver.  Where
in Mythbuntu can I manually check if the correct PID settings have been
acquired?