It causes lockups and freezes because Enigma2 is trying to 
get signal on all ports at the same time.
Also qam256 transponders do not work.

It's best to remove the plugin and configure the tuner
in advanced mode.
Then just use lnb 0 for cable , lnb 1 for dvbt, and 
lnb 2 and rest for all satellites.

For example for cable, set an unused satellite to lnb 0 
and set "universal lnb" to manual and fill in 00000 for 
all 3 values (lof etc).
Disable diseqc and tone mode, then save.

Then choose manual scan and select transponder for scan type.

Inversion on = cable , off = dvbt (or vice versa I forgot :p)

Just scan all cable frequencies one by one by putting a 1 
in front of the frequency.
For example 344MHz should be 1334.
Transponder type should be dvbs not dvbs2.