Distillation

<observations> Date: Jun 14, 2026

🔴 (09:13) User reported a recurring issue ("this just happened again") — pychromecast service on host "labs" (uv[969046]) experiencing nightly Chromecast socket disconnections and AVR probe failures
🔴 (09:13) System involves 3 Chromecast devices: "Entire House" (192.168.50.54 or .15, ports 32141), "Ground Floor" (192.168.50.54 or .15, port 32085), "Home Theater" (192.168.50.54, port 8009)
🔴 (09:13) Chromecast devices alternate between IPs 192.168.50.54 and 192.168.50.15 on reconnect — both appear to be valid addresses for the same devices
🔴 (09:13) Nightly disconnection pattern observed on Jun 11 ~03:19, Jun 12 ~03:20, Jun 13 ~03:30 and ~04:00, Jun 14 ~02:40 — all in early morning hours (meaning Jun 11–14, 2026)
🔴 (09:13) On Jun 14 02:41:36, zeroconf logged: [Errno 19] No such device on socket 7 (('100.69.65.125', 5353)) — OSError in asyncio selector_events.py:1276 sendto (meaning Jun 14, 2026)
🔴 (09:13) Bridge service ("bridge") runs on the system; manages AVR (AV receiver) power and Chromecast streaming
🔴 (09:13) Jun 14 08:38:50: streaming started on "Entire House"; AVR probe returned OFF/no response (resp=empty); bridge sent POWER ON, waited 10s, probed 3 times — all empty; sent volume anyway; set volume to 50 at 08:39:27 (meaning Jun 14, 2026)
🔴 (09:13) Jun 14 08:39:55: AVR probe still OFF while streaming — bridge scheduled stream stop in 60s (meaning Jun 14, 2026)
🔴 (09:13) Jun 14 08:40:57: bridge stopped Chromecast stream on "Home Theater" (app 531A4F84 quit); all devices inactive; turn-off timer fired at 08:41:57; AVR powered off (meaning Jun 14, 2026)
🔴 (09:14) pl2303 module IS loaded on router; usbserial loaded with pl2303 as dependent; /dev/ttyUSB0 exists (permissions -rw-rw-rw-, 224 bytes at 09:41 check); watchdog cron active: */2 * * * * /jffs/scripts/pl2303-watchdog.sh #pl2303-watchdog#; router uptime 19 days 13:23 (no reboot since prior fix)
🔴 (09:14) USB device: Bus 004 Device 002, ID 067b:23a3 (PL2303 adapter); bcdDevice=0305 (PL2303GL/HXN chip variant)
🔴 (09:14) Initial serial read showed echoed PCSEND command packets (POWER OFF, POWER ON, VOL UP bytes) — later determined to be stale TX data in buffer, not AVR responses
🔴 (09:15) User asserted: AVR was physically ON the entire time during the failed probe sequence
🔴 (09:15) stty /dev/ttyUSB0 returns "Inappropriate ioctl for device" with exit code 1 — baud rate cannot be configured on the device
🔴 (09:15) pl2303.ko module strings contain "unknown device type, please report to linux-usb@vger.kernel.org" — driver does not recognize PL2303GL chip type
🔴 (09:15) dmesg shows pl2303 attached successfully ("pl2303 converter now attached to ttyUSB0") but earlier "Unknown symbol" errors from prior failed insmod attempts (

Distillation

Observations