[SOLVED] Stuttering on Raspberry Pi with subtitles

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weff
Junior
Posts: 15
Joined: Sun Nov 26, 2017 5:46 am
Australia

[SOLVED] Stuttering on Raspberry Pi with subtitles

Post by weff » Tue Apr 09, 2019 3:14 am

Hi,

This has had me foxed for a few months now to the extent that I've put the Raspberry Pi aside and reverted to an old i686 frontend.

I've got the Pi 3B with updated mythtv-light version 29 and it plays just fine even in 1080HD. The trouble comes when I enable subtitles (our ears are not as good as they used to be!). Every 10 seconds or so, the audio cuts out or stutters for about half a second. The video seems to be OK (or perhaps we're just more tuned in to the audio).

I've tried all sorts but nothing seems to fix it.

Any ideas out there?

Details are:

Raspberry Pi 3B: /proc/cpuinfo shows:
Hardware : BCM2835
Revision : a22082

mythtv-light-29.1-14-g56030f3f2a-0
Linux raspberrypi 4.14.98-v7+ #1200 SMP Tue Feb 12 20:27:48 GMT 2019 armv7l GNU/Linux
/sys/devices/system/cpu/cpu0/cpufreq/scaling_governor == performance
Video profile is OpenMAX Normal with up to 4 CPUs (having 1 cpu doesn't help).
OpenMAX:HighQuality is worse - sounds like it's coming through a fan!
gpu split is 256 (320 makes no difference)
Audio is ALSA:default (OpenMAX:hdmi is worse)
Dolby/DTS/etc are all off
Upconvert is off (on doesn't help)
Mixer is ALSA:default (OpenMAX doesn't work)

Thanks


Bob
Last edited by weff on Sat Apr 20, 2019 11:23 pm, edited 2 times in total.

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pgbennett
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Posts: 296
Joined: Mon Apr 27, 2015 5:41 pm
United States of America

Re: Stuttering on Raspberry Pi with subtitles

Post by pgbennett » Tue Apr 09, 2019 2:29 pm

Did you try the solution recommended in the wiki?
https://www.mythtv.org/wiki/Raspberry_Pi#Subtitles

weff
Junior
Posts: 15
Joined: Sun Nov 26, 2017 5:46 am
Australia

Re: Stuttering on Raspberry Pi with subtitles

Post by weff » Wed Apr 10, 2019 1:10 am

Yes - I found that with 'threaded' and CPUs=1 or 2, I'd get awful stuttering even without subtitles.

BTW - it's on a hardwired LAN, not WiFi and I'm in Australia, not USA.

I don't know if it's related (it does not coincide with stuttering) but the power 'lightning' symbol comes on now and then. I'm using the adapter that came with the P3B and it's rated 3Amps but also "Made in China".

EDIT: I found another wall-wart, this time rated lower at 5V 2A, but the lightning symbol has gone away. It _seems_ that the stuttering has gone away with 'softblend'. Still bad on 'threaded', mind.

So I'll mark this as SOLVED.

Thanks for your help (again!)

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