Avast Free behavior: ERR_INTERNET_DISCONNECTED

After 20-30 minutes of web use, I get error: Error 106 (net::ERR_INTERNET_DISCONNECTED): The Internet connection has been lost. No connectivity of any type then.

… cycling Avast firewall solves problem for 10-30 minutes (not perfectly consistent.)

If I leave Avast firewall off, problem is non-existent.

Very problematic because I’m doing online courses for college. But this problem is not only happening on courseware. Standard browsing as well.

Windows 7 Home Premium, fully patched. Chrome web browser, lastest patched version.

Thanks for all input

any other security program installed?
what AV did you use before installing avast?

On top of what Pondus has asked - avast free does not have a firewall, do you mean the windows firewall ?