TLDR:
If your fiber box is "old", you will have no connection on the evening and will take multiple months till anyone till deal with it.
My Story:
I connected Odido in July with fiber and realised I have bad connection on the evenings, as i wasn’t home much at that week it took some time to establish a pattern. First time i called support, they obviously got rid of me with "i should send screenshots and proof", which i collected. (worth noting that email address has stopped existing since, so you can only make calls). It took a couple more days of establishing the pattern: around 6pm, i started having tremendously high latency, and very slow loading for sites: speedtest took 2 minutes to load, but then the speed it shown was okay. Sometimes i had no connection, sometimes 0 upload speed, different issues. Anytime i wanted to reach support i had to start explaining from scratch to EVERY support representative, who occasionally switched me to someone else, so the average call length was ~40 minutes. It took about two weeks to get someone who acknowledged finally that this is a known issue with my fiber box and it needs to be replaced, i have been added to a list.
Then a week went by. I called them again, had to explain EVERYTHING FROM SCRATCH in a 40 minute call before support was willing to look into my open case, but no estimate.
Then another week. A month.
Support at this point gave me a voucher for mobile internet (which obviously is not a real alternative to cover a whole house) and 20 euros.
Another month. A third month.
Then finally Guidon reached out and I could select a date.
They came and replaced the box: The man spent 10 minutes in the house.
It was then fixed. It was more than three months since the service started. I could ask for compensation at this point, which they did calculated wrong first and missed promised payment two times.
Fun part comes now...
I have moved to a new address and you wont guess… I have the same issue.
After the third support call they have put me on a waiting list to replace the fiber box without any time estimate. This was 10 days ago, no news since.
I have ordered another provider the next day and cancelled Odido with a month advance, learning from my past mistake.