diff --git a/plex/docker-compose.yml b/plex/docker-compose.yml
index 33624b0..5bd7291 100644
--- a/plex/docker-compose.yml
+++ b/plex/docker-compose.yml
@@ -118,6 +118,12 @@ services:
     restart: unless-stopped
     environment:
       - TZ=${TZ:-America/New_York}
+      # Watchtower v1.7.1's bundled docker client defaults to API 1.25 and
+      # its version negotiation fails against Engine 29 (min API 1.40),
+      # leaving the container in a crash loop. Pinning the API version is
+      # the documented workaround. 1.44 is safely inside the supported
+      # window on this host (server 1.55, min 1.40).
+      - DOCKER_API_VERSION=1.44
       - WATCHTOWER_SCHEDULE=0 0 5 * * *
       - WATCHTOWER_CLEANUP=true
       - WATCHTOWER_NOTIFICATIONS=shoutrrr