Slow video playback/stuttering/slowmotion/asynchronous audio

Hi everyone,

I just registered to this forum because I need help with my video playback. But first let me say I have been using Kodi/xbmc for many years now and I’m very(!) happy with it!

So now here is my problem:

I had Kodi 15.2 running on an Intel NUC (Win10) and Apple iPad 2 (jailbroken iOS 7) for quite some time without a problem, smooth playback on both devices. I use a shared library on my NAS, that’s why both devices need the same version (at least to my knowledge).
The main reason to switch from a RaspberryPi to the NUC last summer was to use SkyGo (Germany PayTV Video OnDemand) on my TV. Until know I had to switch between Kodi and the SkyGo application but then I saw a plugin for Kodi 17 which allows to watch SkyGo in Kodi. So I gave the RC4 a try on the NUC. That worked pretty well and I installed it on the iPad as well. Library conversion/sharing worked like a charm, not problems at this end. But the video playback on the iPad is very “slow” but I’ll come to that. I thought, ok, it’s an RC, wait for the final release.

I installed the final release last week on both devices and the issues persists on the iPad. I made a few changes/test with hardware acceleration and other settings as well as the cache/buffer options (can be seen in the provided log file) but without success.

So here’s what I see:
The video playback most of the time looks like slow-motion and stutters, video and audio are often out of sync especially in fast sequences (video). Playback sometimes stops and/or audio/video are out of sync. It seems like it depends a little on the file, there seems to be files which do not have this issue or at least not that bad. So far I’ve only tested network access but this worked with the old Isengard without any issue and I didn’t change anything else in the setup.
What seems strange to me, when I enabled the logging the on screen debug information showed two CPUs @0% and one “Kodi-CPU” at ~160%. Or is this a normal behavior?

So here is the logfile: http://pastebin.com/ap9p38SS

What I see is some debug information about dropped frames like:

22:13:21.961 T:238264320 DEBUG: CVideoPlayerVideo::CalcDropRequirement – dropped in decoder, lateframes: 54, Bufferlevel: 1, dropped: 1

And some warnings about (buffer) unferflows like
WARNING: DARWINIOS: underflow (0 vs 8192 bytes)

I know I use an old device with and old OS but at least the hardware seems to be fast enough for video playback (because it worked in 15.2), at least that’s my conclusion here.

Any suggestions what to do/change or is it a bug? Or won’t it work on my setup of iPad2 and iOS7?

One options for me would be to move back to 15.2 but I’d like to avoid this and I’m not sure if there is a proper .deb file for iOS since I don’t have the old one anymore.