I can assure you the previous problem, if DVB-C is selected! Yes, the problem there exist!
I did a test, I changed my average tuner from DVB-T to DVB-C, then restart to my dreambox.
The results:
root@dm7020hd:~# cat /proc/bus/nim_sockets
NIM Socket 0:Type: DVB-S2Name: BCM4505Has_Outputs: noFrontend_Device: 0I2C_Device: 0NIM Socket 1:Type: DVB-CName: CXD1981Has_Outputs: yesMode 0: DVB-CMode 1: DVB-TFrontend_Device: 1I2C_Device: 2NIM Socket 2:Type: DVB-TName: PCTV 290eHas_Outputs: noFrontend_Device: 2root@dm7020hd:~#