Very slow download speeds, upload speed normal

I'm not quite sure what the deal is. I have an SB6141 modem and I'm supposed to get 50 mbps download speed, but I'm only getting around 2. The upload speed is fine. All the speed tests were done with my desktop computer plugged straight into the modem.

I've spoken with a Cox rep, power cycled many times, etc. Wondering if a new firmware for the modem may resolve the situation, as it seems to for other users. Or if there are any other tips that may be helpful. A technician is scheduled to come out Tuesday, but it would be great to resolve this.