I've seen the bitrate of the stream be at least 26Mbit/s and I think it's somehow messing with the buffer %filled number.
Windows 7 Laptop (amd e450)
4GB ram, 2GB free during testing
XMBC versions with issue: 13.0 release, 13.1 release, 13.2 beta2
Network share (smb)
2.4Ghz N 72Mbps, 2 feet from router
I've tried a mix of the following advanced settings:
-Putting memory between ~64MB and 256MB
-buffermode 1 or removed
-readbufferfactor 2.0, 4.0, 5.0
These are the same settings I use on my FireTV and my Windows 8 pc and the file plays smoothly.
The thing I find weird is when it is stuttering playback, it looks to me like XBMC has plenty of cache for smooth playback, but still throws the error "cache filled before reaching required amount for continuous play"
In this screenshot the video is playing at ~15 Mbps, and shows a cache size of 64MB, which with rough math should be good for ~30 seconds of playback. It also shows 0% next to cache, which I'm assuming means it thinks it has no cache.
If I play a different encoded source with a lower bitrate 1.5~2Mbit everything works smoothly, the cache fills close enough to the advanced config settings, the % almost always shows 100.
I'm not entirely sure my issue linked to the bitrate of the video, but that's all I have to go on at this time. I'm able to play the video seamlessly on my FireTV at the same time as Laptop is stuttering through playback, so I don't believe it is network bandwidth or disk throughput that are to blame.
I will post a debug log tonight for this, in the mean time please let me know if there is any additional information I can provide.