The speed you get on your service type is largely dictated by your relative distance from where the signal originates. 7.6Mb/s is a little above average for your distance, and while that isn't particularly fast it should be sufficient for a lot general use stuff like browsing, email, youtube, etc.
I've run a ping test to your router and it's reporting about 5% packet loss which I think is probably the source of a lot of the issues you're having. What is causing the packet loss is a little trickier to pinpoint, often times it's a faulty device or faulty wiring - I think doing some real time troubleshooting over the phone is probably the best way to figure that out, if you are up for that. You can get our support team a call at 888.766.4233, or PM me with a good contact phone number and a preferred time to chat and I'll have someone reach out.