I got my Dreamcast Live USB Modem today, plugged it into my Pi, set up everything in Web Browser 2.0 and I got online on the first try! Saw myself show up on Dreamcast Now and even was able to change my avatar/username. About 15 minutes later it disconnected and I have not been able to reconnect since. For awhile I was getting No Dial Tone, but now I'm just getting a No Answer. Decided to try everything on my 2nd Dreamcast, but same issue going on with that as well. Tried swapping out the phone cables with no success. Moved the modem in all the USB slots on the Pi. Both lights are on whenever I attempt to connect. Even re-imaged SD card for the Pi. I do have a Pi 4 so I'm getting the feeling that may be the issue now. When turning the Pi on, only one light is on the modem. It takes several minutes before the 2nd light comes on. Any advice would be much appreciated. Thanks!
EDIT: Spent a couple hours trying to troubleshoot with no luck. IP address is good and does not end in 98 or 99. Swapped modems on the Dreamcasts and tinkered with the internet settings with no luck. I tried using Quake III Arena to set up with no success. Takes about 2 minutes from turning the Pi on for the second light on the USB modem to come on. Takes on average 30 seconds before I get the No Answer prompt when attempting to connect. Both lights stay solid on the USB modem the entire time.
EDIT 2: Turned on Verbose Modem Messages on both Dreamcasts within the Web Browser 2.0 options. Both show OK all the way through, so unsure if either modem is shot. Pinged the Pi successfully from my PC as well.
EDIT 3: Keeping this going as I'm sure people may find it helpful if they face the same issues in the future. I followed all of the troubleshooting guides and everything I could find in this forum yet the issue persists. I'm sending the Dreamcast Live USB modem back to pcwzrd13 to make sure it's good to go. I also ordered 2 working replacement Dreamcast modems off eBay just in case. We'll see how this goes in several days.