Amobia's service is on the decline

For the last 2 weeks Amobia's Internet service has been unstable. Without fail there will be a complete disruption in the Internet connection at least once every evening. The download and upload speeds return back to normal for a few minutes and then reverts to being unstable. This evening I have tried to contact their support desk to no answer after being on hold for half an hour. I have left 2 messages for my call to be returned and have yet to receive a call back from them. I am not sure what is worse atm, the Internet service or the call centre service. Thanks Amobia for the fast declining service.