Having upload speed issues. Download 300+, upload starts at 20-30 and quickly drops to 0. Internet goes off line momentarily after this test. This happens intermittently but looking back at various speed tests its happening about 50% of the time. I’m on Xfinity gateway with Ethernet cable with the 300 plan. Xfinity tech came out and even though the upload was 1.6 said everything was fine. He replaced the gateway but I think he was just trying to close the ticket and leave. He eventually said there was nothing he could do, it’s a back end problem. He starting taking about noise and interference and I accepted all that but brought up the fact the download speed is unaffected. He left, just as well. I then spent another three hours on a chat with the first level support resetting my gateway even though the tech just gave me a new one. Of course that didn’t work and finally it has been escalated to the next level, whatever that means. Anyone have a similar issue before.