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Video saved as wrong frame rate, and audio doesn't correspond to video

I have configured the Bluecherry DVR for 1-hour recording segments. The camera is configured for 30 fps. Audio is enabled in both. The generated .mkv file has video as 60 fps instead of 30. The video stream in the file is 1 hour, 7 minutes 39 seconds (instead of the expected 1 hour), yet the audio stream is exactly 1 hour. Playback of the .mkv file gives video that runs too fast, and I've been unable to deduce a way to sync the video and audio.

I have tried to resample the video with: ffmpeg -i 20-00-04.mkv -r 30 output.mpg which gives me video that runs at the correct speed, but doesn't help with syncing the audio. (That command may resample the audio too, which would be unuseful; I'm not sure.)

Here's the info on the video file. I'd greatly appreciate help producing a video that plays at the correct speed and is synced with its audio. Thanks in advance!

% mkvinfo 20-00-04.mkv

+ EBML head

|+ EBML version: 1

|+ EBML read version: 1

|+ EBML maximum ID length: 4

|+ EBML maximum size length: 8

|+ Doc type: matroska

|+ Doc type version: 4

|+ Doc type read version: 2

+ Segment, size 2875761034

|+ Seek head (subentries will be skipped)

|+ EbmlVoid (size: 147)

|+ Segment information

| + Timecode scale: 1000000

| + Muxing application: Lavf55.33.101

| + Writing application: Lavf55.33.101

| + Segment UID:0x5d 0x4c 0x85 0x63 0x24 0xfa 0xe6 0x31 0x6e 0x09 0xb9 0x57 0x64 0xf9 0xa0 0xe5

| + Duration: 4059.593s (01:07:39.593)

|+ Segment tracks

| + A track

| + Track number: 1

| + Track UID: 1

| + Lacing flag: 0

| + Language: und

| + Codec ID: V_MPEG4/ISO/AVC

| + Track type: video

| + Default duration: 16.667ms (60.000 fps for a video track)

| + Video track

| + Pixel width: 1920

| + Pixel height: 1080

| + CodecPrivate, length 38 (h.264 profile: Baseline @L4.0)

| + A track

| + Track number: 2

| + Track UID: 2

| + Lacing flag: 0

| + Language: und

| + Track type: audio

| + Codec ID: A_MS/ACM

| + Audio track

| + Channels: 1

| + Sampling frequency: 8000

| + Bit depth: 8

| + CodecPrivate, length 18 (format tag: 0x0007)

|+ Tags

| + Tag

| + Targets

| + Simple

| + Name: ENCODER

| + String: Lavf55.33.101

|+ Cluster

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