Shelly 1PM Won't Connect (Stay Connected) to MQTT Distributor

Title says most of it. I can connect a number of other clients to the Distributor, but can’t get a peep out of the Shelly. Debug log of the Shelly says the following…

290992792824 mgos_mqtt_conn.c:472    MQTT0 connecting to
290995429378 mgos_http_server.c:180  0x3fff2914 HTTP connection from
290999151748 mgos_mqtt_conn.c:230    MQTT0 TCP connect error (-8)
290999156445 mgos_mqtt_conn.c:257    MQTT0 Disconnect
290999161022 mgos_mqtt_conn.c:551    MQTT0 connecting after 57034 ms

I have double-checked the user and password multiple times. Even if I allow anonymous MQTT connections, I get the same messages in the Shelly debug log.

Is there some other setting of the Shelly I’m missing? All suggestions appreciated.


Silly me. Firewall issue.