Tvheadend

Hi everyone,

i have a problem with my tvheadend installation and my Digital Devices Cine C2/T2 v7 with two DuoFlex C2/T2 additional tuners. I can only watch streams after reboot. After some time, i cant tune a channel. I only get following error message:

2019-03-16 19:28:31.923 mpegts: 450MHz in DVB-C Network - tuning on Sony CXD2854ER DVB-T/T2/C and ISDB-T demodulator #5 : DVB-C #0
2019-03-16 19:28:31.923 subscription: 0172: "HTTP" subscribing on channel "ZDF HD", weight: 100, adapter: "Sony CXD2854ER DVB-T/T2/C and ISDB-T demodulator #5 : DVB-C #0", network: "DVB-C Network", mux: "450MHz", provider: "ZDFvision", service: "ZDF HD", profile="webtv-h264-aac-matroska", hostname="192.168.177.67", username="admin", client="Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3683.75 Safari/537.36"
2019-03-16 19:28:36.923 mpegts: 450MHz in DVB-C Network - scan no data, failed
2019-03-16 19:28:37.923 subscription: 0172: service instance is bad, reason: No input detected
2019-03-16 19:28:39.923 subscription: 0172: No input source available for subscription "HTTP" to channel "ZDF HD"
2019-03-16 19:28:39.923 webui: Couldn't start streaming /stream/channel/ac4cb94cb16540ea58aa08dac124336e?profile=webtv-h264-aac-matroska, No input detected

But i have no clue why... In the status tab at the streams tab i see very strange signal strength. But why?
Is it a problem with my cabeling? I already tried different cables, always the same.

A log file and a screenshot of the streams tab are attached.

Do someone see something in the log file and can help me?

My TVHeadend version is: Build: 4.2.8-21~g0c36205f7 (2019-03-15T12:47:01+0000)

Thanks in advance!