Page 1 of 1

MP4 file x264 and AAC (LC) audio streams: no sound + other observations

Posted: 26 Nov 2015, 20:19
by loekf2
Hi,

Installed MrMc tonight. Some impressions:

- MKVs with x264 and DTS or DD (AC3) play fine. Bitstreaming works. The ones with a high bit rate (15+ Mbps) look ok. No complaints about framerate (AFAIK these MKVs are all 23.976 Hz).
- AVI files with stereo MP3 or AAC play fine.
- MKVs with stereo MP3 or AAC play fine (might need more testing, think I tried a few files)
- I have a problem with MP4s with stereo AAC. There's no audio, whatever setting I try (passthrough on/off, ATV audio output Dolby Surround or Automatic etc). If needed I can send you a file or point you to the source.
- Scrolling with the Siri remote is real PITA. My Logitech Harmony Eilite is much better. I think the problem is that the touchpad's response to sliding up or down is way too slow. Using the Harmony via IR it's much better, specially if you to scroll through a long list.
- Thanks for keeping the zoom setting. I'm very annoyed that Apple didn't include an overscan setting and though they officially tell devs to maintain a 90 pixels border around their UI vs. the TVs resolution, most apps don't stick to those rules and use the full 1920x1080 real estate. My Philips TV still uses overscan and it's a pain to change scaling mode for each HDMI source.
- SMB access works fine. I can hear continuous read acess from my QNAP NAS, same as Kodi by default on my Shield Android TV. I tweaked the settings for Kodi on the Shield to:

<advancedsettings>
<network>
<buffermode> 1 </buffermode>
<readbufferfactor> 1.5 </readbufferfactor>
<cachemembuffersize> 104857600 </cachemembuffersize>
</network>
</advancedsettings>

which works better for me. The NAS is quiet. AFAIK, you were going to make those settings accessible via UI. Is that still the plan ?

Initial impression... great, but you have to fix MP4 files with AAC audio. Unless I have to change something at my end ???

EDIT: or... did Apple implement perhaps Cinevia ? Hmm... on the other hand, Bluray rips with DTS/DD play fine.

Re: MP4 file x264 and AAC (LC) audio streams: no sound + other observations

Posted: 26 Nov 2015, 20:32
by davilla
need sample of the problem MP4s with stereo AAC. PM or email URL to [email protected]

My QNAP NAS is quiet for me. The whole buffering bit is going to get refactored. Too many buffers at too many different levels also known as the buffer-bandaid.

Re: MP4 file x264 and AAC (LC) audio streams: no sound + other observations

Posted: 26 Nov 2015, 20:37
by loekf2
davilla wrote:need sample of the problem MP4s with stereo AAC. PM or email URL to [email protected]

My QNAP NAS is quiet for me. The whole buffering bit is going to get refactored. Too many buffers at too many different levels also known as the buffer-bandaid.
I will send a sample using iCloud mail and Apple's MailDrop. On my iMac I'm still using Thunderbird. Mail Drop should work.

Re: MP4 file x264 and AAC (LC) audio streams: no sound + other observations

Posted: 26 Nov 2015, 21:04
by amet
tested your sample here, works with passthrough and without it... I see no issues with the sample

Re: MP4 file x264 and AAC (LC) audio streams: no sound + other observations

Posted: 26 Nov 2015, 21:05
by loekf2
amet wrote:tested your sample here, works with passthrough and without it... I see no issues with the sample
Ok, let me check my settings again. Will report back.

Re: MP4 file x264 and AAC (LC) audio streams: no sound + other observations

Posted: 26 Nov 2015, 21:17
by loekf2
loekf2 wrote:
amet wrote:tested your sample here, works with passthrough and without it... I see no issues with the sample
Ok, let me check my settings again. Will report back.
You are right, file plays fine. But I think I found the cause (??) of the problem or better said a better description:

- When you play a MKV with DD/DTS via passthrough, still sound
- Stop the file
- Play another MKV with DD/DTS passthrough, still sound
- Play a MP4 with AAC => no sound
- Then put the ATV into sleep (let it go to sleep mode or forced)
- Wake it up
- Play again the MP4 with AAC, there's sound

My conclusion:

- After you play DD/DTS there's something wrong in the audio device
- Going to sleep and waking up fixes it, of course there's a new HDMI handshake, so the audio device (??) of the ATV is reset

Not sure if it's MrMC or a bug in tvOS

EDIT: looks like the ATV UI sounds, when you go back to home (launcher) are gone as well. Sleep => wakeup brings them back. I didn't test with passthrough off, same sequence (file with DD/DTS, then MP4) yet.