Conection has been dropping for 5 months

My connection has been dropping for 5 months, I'm on a SACM Terayon modem. Just after Christmas I noticed my connection was dropping only for a few seconds then it was kicking back in again, it happens every day about 10-15 times a day. I phoned CS up and they sent an engineer out to check my modem, everything was ok with the modem, he changed the stinger in the cable because it might not be making a connection. Anyway it's still dropping connection and after loads of phone calls to India I'm nowhere close to getting it sorted out.

Now it could be my ethernet connection because I've swapped over from USB to ethernet when I was on USB it was ok but it's a new machine.