Opened 11 years ago
Closed 11 years ago
Last modified 11 years ago
#11530 closed Bug Report - General (fixed)
AirPlay / AirTunes audio stuttering on 0.26
Reported by: | Owned by: | JYA | |
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Priority: | major | Milestone: | 0.26.1 |
Component: | MythTV - Airplay | Version: | 0.26-fixes |
Severity: | medium | Keywords: | airplay frontend stutter |
Cc: | Ticket locked: | no |
Description
I am having a problem with audio stuttering when sending AirTunes? to a frontend. I was using shairport (and still can) without issue. Whenever I send a stream to the frontend, I get what looks like a lot of missed packet errors in the log. I don't have this issue with shairport and just some quick testing of YouTube? videos from an iOS device results in perfect video/audio streaming!
Attachments (1)
Change History (17)
Changed 11 years ago by
Attachment: | mythfrontend.20130506140412.1810.log added |
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comment:1 Changed 11 years ago by
comment:2 Changed 11 years ago by
BTW, airplay audio has ZERO to do with AirPlay? video. Different protocol, different networking, different connection.
comment:3 Changed 11 years ago by
I've been experiencing the same problem since I recently updated my mythtv to the latest 0.26-fixes revision: lots of stuttering when streaming audio from an iOS client (Spotify) to myth over AirPlay? while mythfrontend write the same log messages ("Audio discontinuity seen").
I've also found the change that seems to cause this issue: https://github.com/MythTV/mythtv/commit/5f11bda1994c0dad45ff29e3fc8836eb83f98116. When I revert this single line patch in the current 0.26-fixes revision, AirPlay? works just fine again.
I'm not familiar with the myth audio handling code, so I'm not sure if the patch itself is buggy, of if it just exposes a previously undiscovered bug in the AirPlay? handling code.
comment:4 Changed 11 years ago by
I have a dedicated backend, so I don't know what enabling ipv6 will do, but I enabled it anyway.
The log was from an iPhone 6.1.4 but I've also tried it from a Mac running iTunes 11 with the same results. I've added -v to shairport, but it doesn't log much of anything.
I'll look into the revision at https://github.com/MythTV/mythtv/commit/5f11bda1994c0dad45ff29e3fc8836eb83f98116
comment:5 Changed 11 years ago by
I have a dedicated backend, so I don't know what enabling ipv6 will do, but I enabled it anyway.
The log was from an iPhone 6.1.4 but I've also tried it from a Mac running iTunes 11 with the same results. I've added -v to shairport, but it doesn't log much of anything.
I'll look into the revision at https://github.com/MythTV/mythtv/commit/5f11bda1994c0dad45ff29e3fc8836eb83f98116
comment:6 Changed 11 years ago by
Can you revert commit: https://github.com/MythTV/mythtv/commit/5f11bda1994c0dad45ff29e3fc8836eb83f98116
checkout fixes/0.26 and issue the command: git revert 5f11bda1994c0dad45ff29e3fc8836eb83f98116
and see if that fixes it for you.... thanks
comment:7 Changed 11 years ago by
@jya, just FYI as another data point: I also have issue with audio stuttering as described in this ticket. I can confirm, reverting 5f11bda1994c0dad45ff29e3fc8836eb83f98116 solves issue. I'm on current 0.26-fixes. Test was with iPhome 4 6.1.2
comment:8 Changed 11 years ago by
5f11bda1994c0dad45ff29e3fc8836eb83f98116 fixes a calculation with timestamp. This has a consequence on the RAOP code expiring audio much quicker following the order sync by iTunes/iPhone.
I could easily ease up the test ; but that would cause extra delay in A/V sync. Right now it's pretty spot on...
it's not an easy fix unfortunately :(
comment:9 Changed 11 years ago by
Resolution: | → fixed |
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Status: | new → closed |
comment:10 Changed 11 years ago by
if you guys could try this commit (it will backport easily on on fixes/0.26) and report... If there's no problem, I'll backport it along all the other AirPlay? fixes...
comment:11 Changed 11 years ago by
Priority: | minor → major |
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comment:12 Changed 11 years ago by
I'm running 0.26-fixes. Can I copy the changes and compile there or do I need to check out the head branch?
comment:13 Changed 11 years ago by
I've applied patch 96f58cbf4baa16b2008888f92d4ce2fb7e615aec to the 0.26-fixes branch. I can confirm that this fixed the stuttering completely. Nice work!
Thanks for the quick response!
comment:14 Changed 11 years ago by
Jya, I applied patch to current 0.26-fixes & iPhone4 6.1.3. Songs & Movies playback is flawless. Videos from camera have OK sound - but no video (but video problem for sure isn't related to this ticket). Thx for excellent work!
comment:16 Changed 11 years ago by
Milestone: | unknown → 0.26.1 |
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myth is asking for missed audio packets to be resent, but it never gets the requested packets back.
Please provide a fully verbose shairport playback to see if you get missed packets in the same fashion.
Otherwise, surprisingly, your iTunes machine is connecting via IPv4, the default on all iTunes I've seen is to use IPv6 when available, and myth advertise on IPv6 (shairport is IPv4 only).
if the iTunes client isn't properly setup for ipv6 (only need to enable automatic mode if mac in the network preferences) and let it do its thing.
Also, make sure IPv6 on the mythtv-setup is properly configured to listen on the current local-link address.
In all, it sounds like a misconfiguration of the networking on mythtv side