[ScottEmery]

When I play a video from my NAS, using an SMB share, the video will often stop and a "Buffering %xx" message will appear in the upper right of the screen. The buffering message moves from 0% to 100% pretty quickly, less than 2 seconds, but it is very annoying to have these pop up. I recently upgraded to Eden Beta 1 and now Eden Beta 2. Previous to the Eden upgrades there were no problems with buffering.

Let's see if I can get all of the details here:

XBMC device: AppleTV2 (the black hockey puck)
AppleTV SW: 4.2.2 (2203)
OS Ver: 4.3 (8F305)
XBMC: 11.0-Beta-2 Compiled Jan 20 2012
Free memory: 101MB
The video source is a Synology DS1010+ NAS connected through a Cisco 3750e switch. All wired Ethernet, no wireless.
xbmc.log: Available here http://pastebin.com/S7zj9pZW

Hoping to rule out a networking problem I logged into the ATV2 and preformed an FTP transfer, get, of one of the video files on the NAS which was getting the buffering messages. The destination of the FTP transfer on the ATV2 was /dev/null. Here are the results:

Code:

ftp> get VTS_01_1.VOB /dev/null
200 PORT command successful.
150 Opening BINARY mode data connection for 'VTS_01_1.VOB' (1073739776 bytes).
226 Transfer complete.
1073739776 bytes received in 154 seconds (6983902 bytes/s)

That's 55.9 Mbps which is far above the requriements for ATV2 to play this video. There were also no errors on either of the interfaces, ATV2 nor NAS, in the Cisco 3750 switch.

This seems like a problem with the way that the data fetching/buffering is being done in Eden. I tried to increase the network's cache buffer by setting it to 15MB, but that didn't affect the buffering problem.

In the log file I see the following messages which roughly correspond to when the "Buffering xx%" messages appeared on the screen:

12:55:30 T:166817792 WARNING: CDVDMessageQueue(video)::Get - asked for new data packet, with nothing available

That message sure sounds like a buffer underrun, but I'm no expert on the innards of XBMC.

I'm ready a willing to run experiments or provide more information. Can anybody help?

Scott

[canadave]

My apologies Scott, I'm not sure of the answer to your question. But can I just briefly hijack this thread VERY quickly (and with the full intention of returning it to you) and ask how, when you ran the FTP command from the ATV2, it knew that your file path was referring to a location on your NAS? I've never run that kind of test before, but would be curious to see what mine says.

[ScottEmery]

Dave,

Happy to answer your question. What I didn't show was that I had logged in as root to my ATV2 using ssh and then at the ATV2 command prompt I typed in the ftp command, which includes the IP address or DNS name of the NAS. FTP will ask you for a username and password which is a username and password that your NAS recognizes.

Once FTP is connected to the NAS I typically use alternating "dir" and "cd" commands to locate the file I want to transfer. Note that from within FTP I'm looking at the files on the NAS, not the local ATV2. From there I just issued the "get" command, as shown above. The "/dev/null" destination basically throws away the data that's being transferred from the NAS to the ATV2, and doesn't save it to flash. This prevents the transfer from slowing down.

The command sequence was something like this (starting from a terminal on a Linux machine):

Code:

$ ssh 192.168.1.67 -l root
[email protected]'s password:
Apple-TV:~ root# ftp 192.168.1.21
Connected to 192.168.1.21.
220 192.168.1.21 FTP server ready.
Name (192.168.1.21:root): Scott
331 Password required for Scott.
Password:
230 User Scott logged in.
ftp>

Scott

[canadave]

Ahh, okay, got it--understood. Thanks very much for the explanation, and apologies again for the interruption. Folks, we now return you to your regularly scheduled question

[Ned Scott]

Can you post an xbmc.log file with debugging on? (Settings -> System -> Debug).

[canadave]

In addition to what Ned Scott asked for, I'm curious whether you'd see the same buffering if you connected to your NAS and played the videos via FTP rather than SMB. Might be worth a quick experiment.

[g-off]

You are trying to play a DVD. Try turning off deinterlacing. Sometimes buffering is because it is struggling to decode the video and does not have enough grunt left to stream the data.

Mpeg2 is decoded in software and deinterlacing guts it.

[ScottEmery]

Ned,

I've turned on debugging. The resultant xbmc.log file is here: http://pastebin.com/Yq0RNBAL. Please take a look and let me know what you think.

Dave,

I tried using an FTP source. I got the same buffering problems.

g-off,

I looked far and wide for how to turn off deinterlacing, but couldn't find any option to do this. Can you tell me how to turn off deinterlacing and I'll give it a try?

Thanks for your responses,

Scott

[g-off]

Bring up the osd when playing. There is an option in the settings there. You can even force it as the default.

[ScottEmery]

g-off,

Thank you! I turned off deinterlacing using the OSD and the buffering problem disappeared. I've seen others raising this issue too. Perhaps this workaround should be added to the FAQ on Buffering Issues. Maybe something like: If you are playing MPEG2 video, like a DVD, turn off deinterlacing by using the on screen display when playing the video.

Scott