diff -Nru torchcodec-0.14.0/debian/changelog torchcodec-0.14.0/debian/changelog
--- torchcodec-0.14.0/debian/changelog	2026-10-03 12:22:50.000000000 -0500
+++ torchcodec-0.14.0/debian/changelog	2026-10-25 15:07:45.000000000 -0500
@@ -1,3 +1,12 @@
+torchcodec (0.14.0-1.2) UNRELEASED; urgency=medium
+
+  * d/p/ffmpeg9-flac-cli-block-size.patch: backport upstream test fix, the
+    FFmpeg 9 CLI encodes FLAC with different block sizes so only the decoded
+    samples can be compared with torchcodec's output, not the packets. Fixes
+    the autopkgtest regression with ffmpeg 9.
+
+ -- Sebastien Bacher <seb128@ubuntu.com>  Sun, 25 Oct 2026 15:07:45 -0500
+
 torchcodec (0.14.0-1.1) unstable; urgency=medium
 
   * Non-maintainer upload.
diff -Nru torchcodec-0.14.0/debian/patches/ffmpeg9-flac-cli-block-size.patch torchcodec-0.14.0/debian/patches/ffmpeg9-flac-cli-block-size.patch
--- torchcodec-0.14.0/debian/patches/ffmpeg9-flac-cli-block-size.patch	1969-12-31 18:00:00.000000000 -0600
+++ torchcodec-0.14.0/debian/patches/ffmpeg9-flac-cli-block-size.patch	2026-10-25 15:07:45.000000000 -0500
@@ -0,0 +1,50 @@
+Description: Don't compare FLAC packets with the FFmpeg >= 9 CLI output
+ On FFmpeg >= 9 the ffmpeg CLI encodes FLAC with a block size equal to the
+ number of samples of the first frame fed to the encoder, instead of the
+ default block size for the sample rate used by torchcodec. The decoded
+ samples still match, only the packet layout differs, so skip
+ validate_frames_properties() in that case. Backported to both
+ TestAudioEncoder::test_against_cli and TestEncoder::test_audio_against_cli,
+ which were merged upstream later.
+Author: Nicolas Hug <contact@nicolas-hug.com>
+Reviewed-By: Sebastien Bacher <seb128@ubuntu.com>
+Origin: backport, https://github.com/pytorch/torchcodec/commit/4cf853d18eae6d0a035986bc91dfe46b2a4ad3bc
+Applied-Upstream: 0.16.0, https://github.com/pytorch/torchcodec/pull/1618
+Last-Update: 2026-10-25
+---
+Index: torchcodec-0.14.0/test/test_encoders.py
+===================================================================
+--- torchcodec-0.14.0.orig/test/test_encoders.py
++++ torchcodec-0.14.0/test/test_encoders.py
+@@ -379,7 +379,14 @@ class TestAudioEncoder:
+         assert samples_by_us.duration_seconds == samples_by_ffmpeg.duration_seconds
+         assert samples_by_us.sample_rate == samples_by_ffmpeg.sample_rate
+ 
+-        if method == "to_file":
++        # On FFmpeg >= 9 the CLI encodes FLAC with a block size equal to the
++        # number of samples of the first frame it feeds to the encoder (e.g. 47
++        # for NASA_AUDIO_MP3, whose first decoded frame is short because of the
++        # mp3 encoder delay), instead of the block size that the FLAC encoder
++        # picks by default from the sample rate, which is what we use. The
++        # decoded samples still match, but the packets can't.
++        cli_flac_block_size_differs = format == "flac" and ffmpeg_major_version >= 9
++        if method == "to_file" and not cli_flac_block_size_differs:
+             validate_frames_properties(actual=encoded_by_us, expected=encoded_by_ffmpeg)
+ 
+     @pytest.mark.parametrize("asset", (NASA_AUDIO_MP3, SINE_MONO_S32))
+@@ -2537,7 +2544,14 @@ class TestEncoder:
+         )
+         assert samples_by_us.sample_rate == samples_by_ffmpeg.sample_rate
+ 
+-        if method == "to_file":
++        # On FFmpeg >= 9 the CLI encodes FLAC with a block size equal to the
++        # number of samples of the first frame it feeds to the encoder (e.g. 47
++        # for NASA_AUDIO_MP3, whose first decoded frame is short because of the
++        # mp3 encoder delay), instead of the block size that the FLAC encoder
++        # picks by default from the sample rate, which is what we use. The
++        # decoded samples still match, but the packets can't.
++        cli_flac_block_size_differs = format == "flac" and ffmpeg_major_version >= 9
++        if method == "to_file" and not cli_flac_block_size_differs:
+             validate_frames_properties(
+                 actual=encoder_output, expected=encoded_by_ffmpeg
+             )
diff -Nru torchcodec-0.14.0/debian/patches/series torchcodec-0.14.0/debian/patches/series
--- torchcodec-0.14.0/debian/patches/series	2026-10-03 12:22:49.000000000 -0500
+++ torchcodec-0.14.0/debian/patches/series	2026-10-25 10:39:59.000000000 -0500
@@ -1,2 +1,3 @@
 setup-fix.patch
 0001-Build-against-FFmpeg-9-1607.patch
+ffmpeg9-flac-cli-block-size.patch