Import Audio From Video File gives double speed audio

Cubase
1

I took video on an iPhone and converted it to a format Cubase will import using XMedia Recode. The video imports correctly. The audio imports, but not correctly. The audio appears to be half the length of the video (approximately 49s). The audio seems to be twice as fast. The audio in the video file is mono, but Cubase is creating a stereo file. My Project sample rate and frame rate match the video.

I am new to Cubase. What am I doing wrong?

My system
• Windows 10 Pro, Version 1903, Build 17134.345
• Cubase AI 9.5.40 Build 259, Sep 20, 2018

The MediaInfo data for the file in question is as follows.

Video to be input:
General
Complete name : C:\G.mp4
Format : MPEG-4
Format profile : Base Media
Codec ID : isom (isom/iso2/avc1/mp41)
File size : 19.8 MiB
Duration : 1 min 39 s
Overall bit rate : 1 669 kb/s
Encoded date : UTC 2018-11-04 21:32:42
Tagged date : UTC 2018-11-04 21:32:42
Writing application : Lavf58.19.101

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L4
Format settings : CABAC / 2 Ref Frames
Format settings, CABAC : Yes
Format settings, RefFrames : 2 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 1 min 39 s
Bit rate : 1 500 kb/s
Width : 1 080 pixels
Height : 1 920 pixels
Display aspect ratio : 0.563
Rotation : 90°
Frame rate mode : Constant
Frame rate : 29.970 (30000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.024
Stream size : 18.2 MiB (92%)
Writing library : x264 core 157 r2935
Encoding settings : cabac=1 / ref=2 / deblock=1:0:0 / analyse=0x1:0x131 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=0 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=0 / b_adapt=1 / b_bias=0 / direct=0 / weightb=1 / open_gop=0 / weightp=2 / keyint=299 / keyint_min=29 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=abr / mbtree=1 / bitrate=1500 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=69 / qpstep=4 / vbv_maxrate=2400 / vbv_bufsize=24000 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=3:1.00
Encoded date : UTC 2018-11-04 21:32:42
Tagged date : UTC 2018-11-04 21:32:42
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
Codec configuration box : avcC

Audio
ID : 2
Format : AAC LC
Format/Info : Advanced Audio Codec Low Complexity
Codec ID : mp4a-40-2
Duration : 1 min 39 s
Bit rate mode : Constant
Bit rate : 128 kb/s
Channel(s) : 1 channel
Channel layout : C
Sampling rate : 44.1 kHz
Frame rate : 43.066 FPS (1024 SPF)
Compression mode : Lossy
Stream size : 1.52 MiB (8%)
Default : Yes
Alternate group : 1
Encoded date : UTC 2018-11-04 21:32:42
Tagged date : UTC 2018-11-04 21:32:42

2

Hi,

Most probably the video Sample Rate doesn’t match the project Sample Rate and you didn’t resample. Or the project Sample Rate doesn’t match your Audio Device Sample Rate.

3

Thanks for the quick response!

I believe I had set these correctly before but I repeated as follows to check:

I created a new empty project, set the project video sample rate to 29.97 (not 29.97d) and my audio sample rate to 44.1 khz, bit depth 16 to match the video specs above. Then I imported the above video again. During the import I get an Import Options dialog bus. All options (except “Please, don’t ask again”) are greyed-out and unavailable for selection. I select nothing, proceed, and the Audio track is again half the length of the video track and is stereo while the file contains mono audio.

The video in question does play properly in VLC.

4

Oh, and the VST Audio System driver is Yamaha Steinberg USB ASIO with a hardware sample rate of 44,100 Hz.

I also tried loading video and audio. Audio is too short as before. Then changed project audio sample rate to 88.2 khz. Converted the files to new rate, and replaced them in the pool directory despite warning. Kept audio events at their sample positions.Then changed sample rate back to 44.1 kHz. This time I did not convert. Still kept them at their sample positions. The Audio is now synchronized with the video but down-shifted in frequency (by an octave).

5

Cubase 9.5.41 Build 287 does not fix the problem.

Work around: Set project audio sample rate to 88.2 kHz. Import Audio from video. Change project sample rate to 44.1 kHz. Do not convert the sample and keep it at the sample position. Audio is now synchronized and at the correct frequency.

6

Hi,

I tried to reproduce this, so I recorded a video on my iPhone (6S) and import it to Cubase.

But the result was OK on my side, no issue you described. Could you please share the video with me (use PrivateMessage, and share it via Dropbox or similar, please). It will be used for the testing and development purpose only.

7

So I can’t send the video (don’t have permission from person filmed), and decided to just create a really short test video and send it to you. It did not have a problem! After trying a few things, it appears to be correlated with video length. Cubase does not support the format of any video I create longer than approx 2s, but can import any video shorter than that.

iOS 12.0.1 (16A404)
iPhone Model A1522