TBS6928 and SMIT Viaccess Secure issue

[dvb91]

Hello,

I've an issue with TBS6928 and SMIT Viaccess Secure, descrambling BISTV french provider.
- with SD channels (Viaccess) => OK
- with HD channels (Viaccess Secure) => I soon as I zap on a HD channel, the picture is freezing immediately. After 10 seconds, a new picture appears, and freeze immediately again.

Could you please help me to fix this issue (it seems to be a Viaccess Secure problem)

Regards.
Karim