Pin static-ffmpeg to 9.0.2; drop duplicate stream error log

- ffmpeg 7.1.1's HLS demuxer rejects segment extensions such as .ec3
  ("not in allowed_extensions"), so streams with E-AC-3 audio died a few
  seconds after starting. The image used to track :latest; pinning to
  7.1.1 regressed it. 9.0.2 includes ec3 in the default allow-list.
- The client loop logged the downloader's error a second time (shown as
  "FFMPEG error () - EC: 0") and bumped the error counter twice.

Dockerfile

@@ -19,7 +19,9 @@ RUN XTEVE_VERSION="$(grep -m1 '^#### ' changelog-beta.md | cut -d' ' -f2 | sed '
 
 # Static ffmpeg/ffprobe binaries. To bump, pick a tag from
 # https://hub.docker.com/r/mwader/static-ffmpeg/tags and change it here.
-FROM mwader/static-ffmpeg:7.1.1 AS ffmpeg
+# Do not go below 8.x: 7.1.1 rejects HLS segments with extensions such as .ec3
+# ("not in allowed_extensions"), which breaks streams with E-AC-3 audio.
+FROM mwader/static-ffmpeg:9.0.2 AS ffmpeg
 
 FROM alpine:3.23