When I look in console, I always see these random messages about Avast. They are frequent too. I did a Google search, but did not come up with any conclusive resolution/explanation.
The messages are:
com.avast.proxy[138]: Error reading receive buffer: read(): Connection reset by peer
Those are warnings from the Web shield that inform about a problem when analyzing the web traffic.
There are two reasons, that can cause them:
An invalid HTTP request/response
Webshield bug
There will be some changes/fixes in the next program version, so those messages should became rare. Additionaly, there will be more info printed to the system log on such events.