Hackour wrotenew_user wroteHackour wroteif still the same try to connect the modem directly to ogero box
Is this something I can do by myself or do i need the help of an electrician for that?
you can but better to call an electrician
no one can open ogero box all the works will be outside the box
First connect the modem directly into outlet at home (basically into wall--no filter and try several if you have in the house) and see if you have the same issues. When you do this, try to make it clean and don't have any phones plugged in--lots of times, the filters create more problems and they go bad randomly and suddenly. If you have determined that there is an improvement, start by plugging in one phone at a time (with filter of course) and see if you can find the source of your problem. If otoh you don't find an improvement, get an electrician and plug it in directly into the ogero box and see the results. If there is a significant change, then you probably have an issue with the wiring to or into the apartment, and if there isn't, then the issue is with Ogero/Sodetel on the lines themselves and you could call them and see if they will do anything about it.
In any case, gl.