Tvheadend

Hi there,
for several weeks i'm now working with TVHeadend and love this program. Unfortunately there is one thing i just can't get to work.
First the setting. I am using Mint Linux 18.1 with Kernel 4.8.0-39 on AMD64.
The used TVHeadend Version is 4.0.9-16.
As receivers i habe a Win-TV Nova-T Stick for DVB-T and a
Hauppauge Win-TV-SoloHD. (Triple Tuner for DVB-T, DVB-C and analog)
For both the Firmware is installed and working.
As provider i am using M-Net not Cable Germany, why the predefined Muxes don't work for me.
By the way, this is what M-Nets Homepage sais:
QAM 256
Symbol Rate 6.900
Spektrum from 114-862 MHz

I guess i figured out the the FEC is 3/4 (also tried it with auto)

The general usage of TVHeadend ist known to me, since both sticks work fine, when i am using them on DVB-T.
The predefined Muxes there don't work for me, which is the reason that i am using generic settings, where among the 57 Muxes the ones for Munich are found.
Unfortunately when i am using the DVB-C Tuner with a DVB-C Network i can not find any Muxes that do anything else but FAIL during the scan.
W-Scan works fine and finds all channels available.
Now i searched the internet up and down to find any solution for importing a w-scan channels.conf to TVHeadend.
I also tried to enter Muxes by hand or by editing a predefined MUX-List in /usr/share/tvheadend/data/dvb-scan/dvb-c
Probably i am doing something wrong there.
Here are the first lines of my channels.conf:
rbb Brandenburg:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:601:602+603:28205
rbb Berlin:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:601:602+603:28206
ARD-TEST-1:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:601:602+2602:28221
service_id 28224:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2601:2602+2603:28224
service_id 28225:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2601:2602+2603:28225
service_id 28226:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2601:2602+2603:28226
service_id 28227:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2601:2602+2603:28227
service_id 28228:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2901:2902+2903:28228
service_id 28229:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2901:2902+2903:28229
service_id 28230:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:2901:2902+2903:28230
service_id 28231:314000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:3101:3106+3102+3103:28231
Das Erste:306000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:101:106+102+103:28106
BR Fernsehen Süd:306000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:201:206+202+203:28107
hr-fernsehen:306000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:301:302+303:28108
BR Fernsehen Nord:306000000:INVERSION_AUTO:6900000:FEC_3_4:QAM_256:201:206+202+203:28110

Can anybody either tell me how to import a channel.conf or with which format i have to generate it with w-scan?
What settings do i have to enter into manual MUX-Config that it works with my network?
The parameters i entered were :
Enabled: yes
EPG-Scan: enable (auto)
AC-3 Detection: Standard
Delivery System: DVBC/Annex A
Frequency: 114000000
Symbol Rate: 6900000
Constellation: QAM/256
FEC: 3/4
Advanced Settings: Auto

(and of course several others tries that did not work :-(
Help me please, cause i'm getting desperate sooner or later.

P.S.: The System log only sais: Timestamp mpegts: Frequency (e.g. 317MHz) in Networkname - tuning on Silicon Labs Si2168 : DVB-C #0
which looks ok for me so far