[peterdekr]

I enjoy my Pi (Raspbmc) with my Philips 42pfl7606h tv. I use HDMI Audio passthrough for Dolby. This way my tv decodes the audio, which the Pi probably wouldn't handle.

Unfortunately there is a real bug here: whenever I have a movie that indeed uses Dolby and I pause it, there is a extremely irritating noise/hum that keeps sounding. It sounds like the audio is paused and the last known sample is played repeatedly. It really makes you turn off the volume immediately, which is annoying.

I don't know if this could be caused by my tv, or that it's due to XBMC not properly sending silence or ending the transmission of the audio.

I will try to test with a PC XBMC to see if it still hapens there, but I am wondering if this is a known bug?

Do other people with passthrough enabled have this issue too? Or can you pause without audio problems?

[smanders]

I am having the same problem with OpenELEC 3.2. I posted the details here:

http://forum.xbmc.org/showthread.php?tid...pid1510673

[popcornmix]

Presumably disabling passthrough avoids the problem?

From here:
http://forum.stmlabs.com/showthread.php?...1#pid81081

disabling AVS (a lip sync option) on the receiver fixed the problem.

[edit - fixed link]

[peterdekr]

Presumably disabling passthrough avoids the problem?

From here:
http://forum.stmlabs.com/member.php?acti...&uid=28745

disabling AVS (a lip sync option) on the receiver fixed the problem.

Sorry, did you give the correct link? This is a member profile link.

[popcornmix]

Sorry, did you give the correct link? This is a member profile link.

Ah - the post was by him:
http://forum.stmlabs.com/showthread.php?...1#pid81081

[popcornmix]

A potential fix is out for testing. You will need latest firmware (from master tree).
https://github.com/Hexxeh/rpi-firmware

Download start_x.elf and fixup_x.dat and copy to sdcard fat partition.
You need to add config option "pause_burst_frames=1" to enable the fix.

If testing is positive I'll make it default option.

Even if you don't have this issue, I'd appreciate testing the new config option, to ensure it doesn't break anything.

[peterdekr]

Great, it is fixed with this solution! I can now pause correctly while having Dolby Digital passthrough audio.

[Sjakie]

Hi, I would like to test the fix but I don't have a clue what I have to do.
On the RPi i can only find files named start.elf en fixup.dat. The files both are located in /flash and /usr/share/bootloader. I assume they have to be renamed?Also I don't know in which file to put the config option. I search the wiki for this, but I could not find an answer, doesn't mean there isn't one, it can also be me, lacking reading skills . Anyway, I would be most grateful if someone would point me to the right article, or shares the solution.

[popcornmix]

Hi, I would like to test the fix but I don't have a clue what I have to do.
On the RPi i can only find files named start.elf en fixup.dat. The files both are located in /flash and /usr/share/bootloader. I assume they have to be renamed?

Yes rename them to match the files that are there.

Also I don't know in which file to put the config option. I search the wiki for this, but I could not find an answer, doesn't mean there isn't one, it can also be me, lacking reading skills . Anyway, I would be most grateful if someone would point me to the right article, or shares the solution.

I assume you are using openelec? Just insert sdcard in a PC sdcard reader, and you should see the contents of the FAT partition (what you see as /flash from the pi).
Just replace start.elf/fixup.dat and open config.txt in notepad, and add the suggested line.

[Sjakie]

Yes, using openelec 3.2.3 ( sorry)

Well, guess what.
It works!!!! awesome!!
If you need more information on my setup, or anything let me know. for now I'm really happy.

Unfortunately this was only temporary...

well...the fix works for the particular problem of the terrible noise, but introduces a new problem. I experience audio drops every few seconds.
This was on a different file, a mkv-file of the Adele concert in Royal Albert Hall. The noise problem has not occured with this file
I undid the fix because I rather have the screeking noise after pausing than the whole concert (or movie) audiodrops.

so in a nutshell

before fix:
- noise while pausing a DOLBY DIGITAL 5.1 televisionshow ( The Walking Dead S04E03 720p HDTV x264-KILLERS.mkv )
- no audio drops on Adele Live in the Royal Albert Hall.DTS.mkv

after fix

- no noise while pausing television show.mkv
- audio drops every few seconds on the concert.mkv

I hope you can use this information.

[wiesel]

A potential fix is out for testing. You will need latest firmware (from master tree).
https://github.com/Hexxeh/rpi-firmware

Download start_x.elf and fixup_x.dat and copy to sdcard fat partition.
You need to add config option "pause_burst_frames=1" to enable the fix.

If testing is positive I'll make it default option.

Even if you don't have this issue, I'd appreciate testing the new config option, to ensure it doesn't break anything.

dont works for me (openelec 3.2.3)

1. downloaded start_x.elf and fixup_x.dat
2. renamed start_x.elf and fixup_x.dat to start.elf and fixup.dat
3. replaced start.elf and fixup.dat in the /flash folder
4. wrote "pause_burst_frames=1" in the config
5. reboot
6. installation broken -> Pi dont boot

I'm doing something wrong?

sorry for my english