I had a customer call with upload issues, didn't find any issues with his, but the sector he was connecting to only negotiated 10Mbps, thousands of FCS errors in a few hours. Upgraded from 6.42.1 to 6.42.6 and the problem persisted. Downgraded to 6.41 and I've got a 100Mbps full duplex link with zero errors.

Anyone else seen behavior like this?