Raspberry pi 1 Issues Sound stutter and 1080p freeze

I have 2 problems on my raspberry pi 1 512mb.

  1. after a few minutes sound stutters for about 2-3 seconds, then plays fine. I am playing h264 720p content over HDMI using latest OSMC version

  2. when playing 1080p - setting resolution of Kodi to 1080p (instead of DESKTOP in menues - default) - Kodi just freezes in half an hour

I have downclocked the Raspberry to 700/250/400.

The problem 1) I also had on Raspbmc, but with an Firmware patch it went away - patched the bin file. How to do this on OSMC?

The problem 2 is just wierd. Even playing 1080p content on DESKTOP resolution settings - default - the info on my TV screen resolution stays 720p, so the 1080p content is really not working. Only when I change it to 1080p in menues, then it is really 1080p. Is there no way to autodetect and change playback resolution on the fly?

I also have no problem to always have it in 1080p but then the problem 2) ocurrs - freeze after 30min.

OSMC has a much later version of the Pi firmware than Raspbmc - we keep the firmware up to date so attempting to patch it is not going to help you.

Kodi does not change resolution on the fly - it will scale the content to whatever resolution you have set. So if you want to get full 1080p quality you should set your Kodi resolution to 1080p. Then when you play lower resolution files they will get scaled up to 1080p using a high quality scaler.

How do I debug stuttering sound? Or 1080p crashing after 20min of playback?

How are you serving the data?
Locally?
Over a network?
What is the media? > http://sourceforge.net/projects/mediainfo/

What card do you have in the pi?
class 10? class 4 ?

Grab some logs
To get a better understanding of the problem you are experiencing we need more information from you. Please see http://osmc.tv/wiki/general/how-to-submit-a-useful-support-request/ for advice on how to help us.

The biggest unknown that I see is that both things started happening as I switched from Raspbmc to OSMC.

I am serving it through powered usb hub from a usb ntfs formatted hard drive. I know it is not optimal for linux but ocassionally i use it on Windows maschine, thats why it is in NTFS.