First, I apologise if this is not where to put live-cd issues. Second, I have no explanation whatsoever for why it works every other time, but I've spent two weeks attempting to install Gentoo, and every failure that wasn't a failed packaged was related to eth0 and pppoe. This particular bit is the one I can't figure out, pppoe (rp-pppoe) fails every other time. I setup with pppoe-setup exactly the same, I then type "sudo pppoe-start && sudo pppoe-connect" I then test it with ping and traceroute No matter how long the system has been off, or just not yet connected, and I find it BEYOND bizarre, it fails exactly every other time. I always get "PAP authentication succeeded" and pppoe-status on connect always only varies with received and transmitted at 3,4 and 6,8.
Please, attach a log for both the succeeded and failed attempts and reopen then.