Mac + Xbmc 12.1/12.2 - Live TV problems

[unfledged]

Hi there,

I'm having problems with live tv buffering on my Mac XBMC setup. When I start to play a live stream, it plays absolutely fine for around a minute. Then it will pause and start buffering, but the buffering never progresses past 0%. After another minute, the stream ends and XBMC returns to the menus.

This is only happening on my Mac setup (10.8.3) - live tv works fine on two linux boxes and on an iPad on the same network. It even works fine when bootcamping the Mac into Windows. It also only occurs with XBMC 12.1 (which I skipped over due in equal parts to this and audio issues) and 12.2 - the original 12.0 release of Frodo, which I still have installed alongside the latest, continues to work fine.

If it's of help, I have a full debug log at http://pastebin.com/mtmp6Dft.

Any ideas?

[planetix]

Try setting a minimum audio cache. Add this to advancedsettings:

<pvr>
<minaudiocachelevel>20</minaudiocachelevel>
</pvr>

Also make sure "Sync playback to display" and "Always" are set in XBMC options.

[unfledged]

Thanks for the suggestions, unfortunately no improvement

[unfledged]

Sorry to bump this, but does anyone have any other suggestions for this problem - whether that be possible fixes, debugging steps or just suggestions at what area to consider for fixing this! It's a very annoying problem I'd love to overcome!

[Red_F]

This sounds like something native to just (a configuration within) OS X. Since the problem isn't there when you run Windows on the Mac, your hardware is not the problem.

Unfortunately my 'Mac' is just a OS X running on VirtualBox. It allows me to compile XBMC and the addon and run it to see that it functions. But performance of my emulated Mac is so bad that I can not use it to see how smooth (or not) things are on a real one.

Did you try asking other Mac OS X users on the xbmc forums?

[unfledged]

Thanks for the reply.

I have posted in theXBMC > Argus TV Plugin forum about this (though I didn't include the deub log - which I didn't have at the time - in the post) - http://forum.xbmc.org/showthread.php?tid=152019 - another Mac user in that thread with the same issue, though. Even without a debug log, that thread hasn't gained any interest either in number of view or (especially!) replies.

Just out of interest, and with your post sending my mind down a new track for where the issue could be coming from, did the Argus TV plugin change between XBMC 12.0 and 12.1? If so, it could well indicate a plugin problem. If not, a change in XBMC would seem most likely to blame.

Is there anything I can offer to help you test on OS X in the future, up to and including a remote test server (if you know how I could enable such access)?

[unfledged]

I sort of answered my own question. After putting the 12.0 version of the Argus Tv plugin into 12.2 the problem still remained. This suggests the issue is as a result from XBMC changes, rather than plugin changes. As such, I've started a new thread at http://forum.xbmc.org/showthread.php?tid=164366. Hopefully that might get some good suggestions!

However, my instinct is that this is primarily an Argus TV (or at least its plugin) problem rather than an XBMC one (even one cause by changes within XBMC) due to not only it working fine with 12.0 but also because, in the time between my original post and now, I tried a NextPVR setup on my server which was able to play live tv fine. If it wasn't for the fact it's incredibly inferior to Argus TV I'd now be a happy bunny. As it is, if there is anything else I can do to get to the bottom of this, please do let me know.

I've found workarounds (most notably starting a recording of any channel I want to watch live, and then fast forwarding to live), but I'd much rather have it working as intended.

Edit: updated to say it is my instict that this is an Argus TV problem, rather than being convinced thereso.

[Red_F]

Actually, the addon is using file I/O functionality for samba shares that are provided by XBMC. These may have changed between version. Other users are having issues too, but those look to be related to network topology (eg. switching the same client system from wired to wireless -or vice versa- causes the problem to appear or disappear).

Therefore it may very well be a problem deeply within these routines inside XBMC. Sadly (or luckily) none of the various test systems I have available ever showed any of these problems....

[unfledged]

Very interesting.

Do all of the functions of the plugin use this same i/o architecture? (And in broadly the same way?) I ask as the only area that has any issues is that of live tv - recorded tv (even recorded tv in progress being fast-forwarded and watched live) does not show this issue. If that's the case, it would suggest that there is something different about the live tv element's approach, or XBMC's architecture when accessing the live tv file (presumably the same buffer file which has caused so many issues in a separate thread in this forum.)

Edit: my Mac client is being used for other purposes at the moment, but when I get chance I'll try switching it to a wireless connection to see if that makes any difference. If so, this could well be another example of said problem.

[Red_F]

No, not all functions are using the same file I/O.

Recordings are stored on the ARGUS TV shares. To play a recording the addon passes the UNC filename to XBMC. XBMC then uses its standard internal player (or -on Android- its standard external player ) to play the file.

Live TV works differently. When watching Live TV, ARGUS TV creates a set of buffer files (.ts) where it writes the MPEG stream. A metafile (.tsbuffer) is continuously updates with filenames, write positions and checks. XBMC repeatedly asks the addon to supply blocks of data from the video stream (usually 32K). The addon uses the XBMC file I/O support to read the metafile, build a continuously refreshing list of buffer files and the current write pointers. Then, using these buffer structures, the addon uses the XBMC file I/O support to read the correct parts from the relevant buffer files on the ARGUS TV timeshift shares.

The internal code used to read the Live TV files are identical for all non-Windows platforms (Linux, OS X, Android and iOS).

So, yes it is very well possible that viewing recordings works flawlessly while watching Live TV fails. The XBMC file I/O support are new to Frodo (12.x) and have been introduced very late in its development cycle.