Frequent Dropouts with Newest Linux Kernel Version

Audio Gear Talk Raspberry Pi
1

Raspberry Pi3 R
Running kernel 4.4.17-v7+
Raspian 8.0
Using the onboard wifi

I was having no trouble until upgrade-itis hit, and I ran an update to the kernel. 4.4.6 was streaming without any dropouts, but this latest kernel is terrible.

I found a few threads on the PI forum talking about the terrible WIFI capabilities on the PI3. I’ve disabled Power Management as that was one of the suggestions to improve WIFI (3/4 down the page here: https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=138312)

I’ve heard that the issue might be that because I’m using USB Audio, and because wifi and USB are on the same BUS, I’m going to have issues.

Any suggestions to fix this? Either software or hardware based. Should I buy a powerline adaptor? (https://www.netgear.com/home/products/networking/powerline/?cid=wmt_netgear_organic)

Got a favorite?

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I can’t say for sure, but as it was running without any issues before the kernel upgrade, I don’t think it is related to Wifi+Audio sharing the usb bus.

The wifi chip on the pi3 should not use the usb bus. you can see this by running ‘lsusb’

Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

So ethernet is implemented on the USB bus. The internal Wifi chip uses (afaik) the sdio bus. (but it is not very fast).

You could use a better USB wifi dongle in combination with a Hifiberry/IQAudio audio card (connected on the gpio header).
But before doing so, I’d try it with a new linux installation (maybe on a separate sd card, to be able to revert back to your current system).

1 Like
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Thanks @crieke for the confirmation on the usb bus question! Crazy how misdirected you can get within forums.

I’m trying to avoid the Hifiberry route only because I’m going into a NAD D3020, which has a nice sounding DAC in it already.

I’ll give the new linux install a try. Is Raspian the best choice, or have people had any luck with any of the audio specific distributions?

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I can understand that. As the Hifiberry/IQAudio and also the Raspberry Pi boards are not very pricey, you could also reuse them for another zone (a nice kitchen Internet-Radio?). :wink:

5

Hello

I bought the Hifiberry Digi+ which sounds ridiculously good considering it costs just over £20. It does not have a DAC, so you can feed it into whatever you want, and you will not be duplicating anything. It worked straight out of the box, and stands comparison with systems costing ten times the price or more!

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Sweet tip. I hadn’t noticed the digi + before. Thanks for that.

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I’ve also been having some dropout issues on Raspbian Jessie Lite since updating to the latest Linux kernel with rpi-udate. I fiddled with the Wifi power management, which may have helped somewhat, but the dropouts still happen (possibly less frequently). I may try the IQaudIO SD image instead Raspbian/RoonBridge next week to see if that helps. This will likely also change the linux kernel, conflating the possible variables, but if it works I’ll be happy.