Your package loss red, may not be real, the Fritzbox routers have a habit of showing lots of packet loss when that is not the case i.e. it decides to not respond to the ping box at times.
If this was real packet loss would usually expext to see the yellow/blue and green areas showing a lot more variation
If the Fritzbox dropping the sync in addition to the PPP session being dropped?
04.12.18 11:29:49 Internet connection established successfully. IP address:
xx.xx.xx.xx, DNS server: 126.96.36.199 and 188.8.131.52,
gateway: 184.108.40.206, broadband PoP: acc-aln1.bdb
04.12.18 11:29:41 No automatic configuration or updates by the service provider
possible for this device: Timeout.
04.12.18 11:29:38 Timeout during PPP negotiation.
04.12.18 11:29:38 Internet connection cleared.
04.12.18 11:28:33 No automatic configuration or updates by the service provider
possible for this device: Timeout. [57 messages since
It may be that PPP echo is being missed and router dropping connection to reconnect things.