Tuner problem with 6991SE !!!!

[apolon]

i have instaled last drivers for this card and all working good , am use mumudvb 2.0.0. last version .

tuner A working normaly but tuner B not working !!!

Info: Tune: LNB voltage 18V
WARN: Tune: problem to set the LNB voltage
WARN: Tune: DISEQC SETTING FAILED
Info: Main: Tuning issue, card 1
Info: Main: Closing cleanly. Error 7
Info: Main: ========== MuMuDVB version 2.0.0_20150103_mumudvb2 is stopping with ExitCode 7 ==========

am try many configuration but not working

any have this problem??