Spotted this error in the logs:
2020/11/27 18:00:43.941107 [SYS] Starting Channels DVR v2020.11.27.2225 (linux-x86_64 pid:202) in /home/ubuntu/channels-dvr/data
2020/11/27 18:00:43.967998 [SYS] Started HTTP Server
2020/11/27 18:00:44.494311 [HDR] Found 2 devices
2020/11/27 18:00:44.889360 [ERR] Failed to refresh auth: invalid character '<' looking for beginning of value