Audio Distortion Using Official Roku App Via Optical Output

[Gaz 20]

Hey guys, hoping some of you may have come across this issue in the past and know of a fix!

 

I connected my Roku up to a set of 2.1 speakers Santa got me for Xmas and have an optical lead connected to the Sub direct to the optical port on the back of my TV. Whenever I playback any media via the Emby app for Roku I get really bad audio distortion whenever low or high level audio levels are playing.

 

I tried the Emby app for my Samsung Smart TV and it doesn't do this, the sound is perfect.

 

I also tried the Roku Blue Neon Night App and the sound didn't distort like it does on the official Emby for Roku app, but it did sound compressed and lagged and nowhere near as good as it did when using the Emby for Samsung TV app.

 

I tried changing all the audio settings in the Blue Neon Night app to see if I could get the audio output to sound better but couldn't.

 

I couldn't find any audio options on the official Emby for Roku App so guess I can't use that anymore and it made me wonder why the Blue Neon Night app for Roku seems to handle audio better than the offical Emby for Roku app?

 

Is there anything I can do to help get rid of the audio distortion and keep using the official Emby for Roku app?

 

I love my Roku but fear it will become a glorified paperweight if I can't get the sound to playback correctly

 

My Samsung Smart TV is connfigured to output audio via PCM stereo as is my Roku 3 as I'm using a set of M-Audio 2.1 powered speakers and subwoofer.

 

I'm using Shark007 codec pack, I set it to the recommended install so not sure if there's anything I need to reconfigure in the codecs to help with the sound??

 

Any advice would be very much welcomed and thanks for taking the time to read my post, cheers

Edited December 26, 2017 by Gaz

[ebr 14910]

I've never heard of this but I'm thinking the solution may lie somewhere in the audio settings for the TV or Roku device.  I would play with different combinations of those settings.

 

 

 it made me wonder why the Blue Neon Night app for Roku seems to handle audio better than the offical Emby for Roku app?

 

I also tried the Roku Blue Neon Night App and the sound didn't distort like it does on the official Emby for Roku app, but it did sound compressed and lagged 

 

?

 

Also, I don't understand the reference to Shark codecs...  You have these installed on the Roku?

[Gaz 20]

Thanks for the reply ebr

 

The audio settings on the TV are simply PCM or Dolby Digital. I've tried every combination trust me of these mixed with every combination of audio settings on the Roku (PCM, DD, DTS, DD+ etc) but still the problem exists

 

The only way I can get perfect audio is by using the Emby for Samsung TV app, but it's ugly and slow and not nearly as nice as the Emby for Roku app so I'm loathed to have to use it if you know what I mean.

 

Just wondered why the Emby Neon Night Roku app has better audio playback than the Official Emby for Roku app, there's no audio settings availalbe on the official app to even try different settings

 

I only mentioned the Shark codecs in case specific codecs had to be selected/used for transcoding audio when streaming from my PC to the Roku etc. I don't know if they are even part of the equation tbh!

Edited December 27, 2017 by Gaz

[Waldonnis 148]

I have a similar setup on one of my televisions: television connected via optical to a powered 2.1 speaker setup (has its own built-in amp and crossover, similar to a basic soundbar). Just to cover the usual bases - make sure you double-check or try swapping your cabling to eliminate those as a potential cause.  I'd check the Roku's HDMI cable first, since it sounds like the optical cable is performing okay if you're not hearing distortion when only the television's involved, but it couldn't hurt to verify that the optical connectors are properly seated as well.  Also, if your external speakers have separate volume control, be sure to set the television to fixed volume output and that the internal speakers are turned off (basically just to stop the television from using its own amplifier).  I doubt that's a problem, since you would hear distortion even when playing something on a television app, but worth checking.

 

Is this transcoded audio or direct?  Also, what codec and channel layout is the audio you're trying to play?  I only ask because the Roku can only pass through certain codecs and ffmpeg's defaults when downmixing can introduce some clipping or distortion in some cases.  The worst offenders for me seem to be 5.1/7.1 lossless sources with orchestral soundtracks (like Star Wars films), but I've heard it with others as well when I let ffmpeg transcode those tracks with the defaults (basically, when only using -ac 2 without adding a custom pan filter string or other such modifications).

 

Oh, also, do the television and soundbar support ARC and can the soundbar decode codecs like DD (AC3) on its own?  If so, it may be a better/easier connection option and has greater bandwidth potential compared to S/PDIF (and eliminate the need to transcode codecs that can be decoded by the soundbar but not the television).

[Luke 37050]

Can we look at some examples of files that sound differently between the two Roku apps? Please attach the information requested in how to report a media playback issue. thanks !

[Gaz 20]

@@Waldonnis - thanks for the reply. First thing I did after the initial audio issues was to swap out both the optical cable and the HDMI just to check. As I said previously there's no audio distortion issues using the Emby Neon Night Roku App, only when using the Official Emby App.

 

I'm also using 2.1 powered bookshelf speakers and a sub (M-Audio AV32.1) http://www.m-audio.com/products/view/av32.11 and connecting the subwoofer to the back of the Samsung Smart TV using a securely fitted optical cable.

 

Most of the movies/tv shows I've tried so far are .MKV files and all of them suffer from audio distortion using the offical Roku app. It's not quite as bad on AAC Stereo files as it is say on DTS 5.1 and Dolby 5.1 encoded files, the latter are totally unwatchable due to the extreme levels of sound distortion.

 

I installed the Shark007 advanced Codec pack on my PC but don't know if it needs to be specifically configured/optimised when streaming my media from my PC to my Roku via the Emby app. I just chose the default recommended settings and went with that (excuse my ignorance).

 

I've attached some recent logs if it helps?

 

Thanks again for the help guys, much appreciated and hope you're all enjoying the festive season

 

Cheers

recent_logs.zip

Edited December 27, 2017 by Gaz

[ebr 14910]

Hi.  We need to know what logs go with what playback.   So, you would need to play something one way, record the experience and label the logs generated then do it the other way and post both out here so we can know which logs go with each experience.

 

I know DD+ will not pass over optical cable.  Perhaps the official app is trying to do that but we need to see specific examples to try and diagnose.  Thanks.

[speechles 1917]

@@Gaz When trying to manipulate the audio codec it must be transcoding. Direct play will, well, direct play the codecs as is, the settings for audio are not used in this case. So change the play method to "Force Transcode" which will allow stream copy of the video stream. This will then change the audio codec to the one chosen in settings. Using "Auto-Detection" may transcode the audio and copy the video stream, since yours use DTS and your roku reports it only supports 2 channels. Does your TV not support HDMI-ARC output to feed to your soundbar?

 

The Official app allows ac3, mp3 or aac to direct stream, and if it has to transcode the audio will always default to MP3 for 2 channel (the end user cannot change this behavior).

 

The blue neon app allows ac3, mp3 or aac to direct stream too, and you can easily force the app to transcode to a codec instead of the default AAC for 2 channel. Have you tried using "AC3" as the default codec and does this still produce the same audio defect? Does it produce silence, meaning your setup doesnt support it? AC3 and DTS are the only codecs the roku will pass-through without manipulation by the roku firmware. 

 

The main difference between the two apps is by default blue neon chooses AAC, and the official app chooses MP3. This in itself is likely the cause of the problem.

 

There is only one device that can support DD+ (EAC3) and that is the 2016 roku ultra. It will convert DD+ to DD on the roku ultra directly on-the-fly. The 2017 roku ultra does not support optical out, or DD+ in any fashion.

 

Also, think of the blue neon app as a testing bed. The reason it has so many options is to future proof the app. If in the future the guys at roku make a mistake and their firmware update breaks anything, there should be options for the end user to hopefully correct those defects. There are also settings to allow h264 to pass-through in 4k (which no roku model supports, yet?) and options to allow pass-through of HD codecs, trueHD/DTS-HD MA (which roku also doesn't support yet!). So the blue neon app is more useful for users to debug their own problems. Have you used the "Device Info" button which shows up on the options row as a circle with a question mark in it? Scroll down to the bottom of the "Device Info" screen until you see [Audio Decode Info] section. In this part you can tell what your roku is seeing as supported. For example: AC3: 6:0:0:1. The first 6 means how many channels are supported. In this case 6 is shorthand for 5.1. Then the last digit is the pass-through option. A 1 at the end means the roku passes this through unaltered in any way. Using this screen you should be able to see the supported codecs for your roku easily. You can also enable debug in the app settings. This will create a "Debug Logs" button on the options row. Looking through this will help explain why the app usually isn't at fault for the issues and will point fingers directly at the roku firmware as the root cause. Using these "tools" in the blue neon app will help you be your own detective. Since you are the one experiencing the issue and not anyone else this is why the app lets users have so much control. You are the best person to debug your issue.

 

Any questions feel free to ask. I will also have a new version of the blue neon app to fix some bugs I have found in the app. Stay tuned...

Edited December 27, 2017 by speechles

[Gaz 20]

@Speechless - thanks so much for taking the time to explain in such detail the audio options in Blue Neon Night, it was really very much appreciated and very helpful indeed

 

I set AC3 as the default audio codec and I got silence which assuming I'm using a set of 2.1 powered speakers probably doesn't come as a shock eh!

 

I'll stick with your Blue Neon app as it has extremely useful features and as you say, let's the end user do their own testing and custom setups.

 

Just a real shame that the 'official' app has no customizable options but I'm guessing the devs locked this down to stop increased forum posts etc.

 

If only there was a way to change from MP3 to AAC on the official app!

 

Oh and the latest Roku Streaming Stick + supports 4k playback - https://www.roku.com/en-gb/products/streaming-stick-plus

 

Big thanks again for the help guys and a happy 2018 to you all

Edited December 29, 2017 by Gaz

[Luke 37050]

@Speechless - thanks so much for taking the time to explain in such detail the audio options in Blue Neon Night, it was really very much appreciated and very helpful indeed

 

I set AC3 as the default audio codec and I got silence which assuming I'm using a set of 2.1 powered speakers probably doesn't come as a shock eh!

 

I'll stick with your Blue Neon app as it has extremely useful features and as you say, let's the end user do their own testing and custom setups.

 

Just a real shame that the 'official' app has no customizable options but I'm guessing the devs locked this down to stop increased forum posts etc.

 

If only there was a way to change from MP3 to AAC on the official app!

 

Oh and the latest Roku Streaming Stick + supports 4k playback - https://www.roku.com/en-gb/products/streaming-stick-plus

 

Big thanks again for the help guys and a happy 2018 to you all

 

hi @@Gaz, please provide the information @@ebr requested in post #7. Thanks !