I purchased SVP 4 Mac few days ago and been trying to make it work for me but I'm having issues with audio-video desync in mpv. Anytime I seek forwards or backwards in the video, the A/V is synced perfectly but over time gets desynchronized no matter the options I tried.
The only configuration I changed in SVP 4 Control Panel is following:
Frame rate conversion fixed to 60 FPS
Quality slider moved all the way to the right towards quality, but tried lower quality as well with same results
Optimized for animation
Low artifacts masking
When it comes to hardware and software, I'm running SVP on this machine:
iMac (27-inch, Late 2012)
3,4 GHz Intel Core i7
8 GB 1600 MHz DDR3
NVIDIA GeForce GTX 680MX 2048 MB
macOS 10.12.2
/usr/local/Cellar/mpv/0.23.0_2 (61 files, 33.5M) * Built from source on 2017-01-10 at 23:22:21 with: --with-bundle --with-vapoursynth
/usr/local/Cellar/vapoursynth/35_1 (22 files, 2.8M) * Poured from bottle on 2017-01-10 at 22:19:31
/usr/local/Cellar/mvtools/HEAD-a2f5607_1 (4 files, 659.3K) * Built from source on 2017-01-10 at 22:19:30
So a fairly beefy machine that should be able to handle SVP – I mean, before purchasing SVP I was running custom Vapoursynth script without any issues and that one didn't use GPU acceleration (obviously). I should mention that this issue occurs not only with 1080p videos but also with 720p (neither of them are Hi10P). I obviously shouldn't link the video that was giving me hard time but let's say it was 720p rip of eighth episode of Kono Subarashii Sekai ni Shukufuku wo! and for some reason the filename also contained string “HorribleSubs”. Wink wink.
Finally, when it comes to mpv.conf, I started with minimalistic config file found on Wiki (input-ipc-server=/tmp/mpvsocket hwdec-codecs=all hwdec=auto-copy) all the way to this monstrosity:
input-ipc-server=/tmp/mpvsocket
hwdec-codecs=all
hwdec=auto-copy
vo=opengl
opengl-pbo
dscale=mitchell
correct-downscaling
sigmoid-upscaling
icc-profile-auto
icc-contrast=1000
tscale=catmull_rom
dither-depth=auto
blend-subtitles=yes
video-sync=display-resample
video-sync-max-video-change=10
autosync=30
border=no
osd-font='Helvetica Neue'
idle=yes
keep-open=always
ytdl-format=128+bestaudio/266+bestaudio/264+bestaudio/299+bestaudio/137+bestaudio/298+bestaudio/22/135+bestaudio/18/best
sub-codepage=cp1250
slang=enUS,en,eng,csCZ,cs
alang=jp,jpn,enUS,en,eng,csCZ,cs
At the end (starting with border=no) is my old configuration file, everything above that is something I found here on the forums and decided to try but to no avail. Tried different values for video-sync, nada.
Oh, one more thing: this is how the performance monitor looked like during playback and this is the last line in mpv's console after 3.5 minutes of playback: “(Paused) AV: 00:03:25 / 00:23:40 (14%) A-V: -0.000 DS: 1.000/0”. If I understand things correctly (not sure!), based on the A-V value mpv things audio and video are perfectly in sync when in reality, audio is delayed by roughly two seconds at this point!
If I can provide you with any other data necessary for debugging and solving this, please let me know. I really want to have this issue resolved, can't live without my 60 FPS videos anymore