USB Audio Adapter - crackles

Moderators: adafruit_support_bill, adafruit

Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
Locked
User avatar
danstuart
 
Posts: 2
Joined: Fri Dec 20, 2013 11:39 am

USB Audio Adapter - crackles

Post by danstuart »

Hi,
I’ve installed this adapter successfully, and got it working, using your guide.
http://www.adafruit.com/blog/2013/09/17 ... pberry-pi/

But unfortunately the device just crackles the whole time it’s playing audio! Unusable really.
I’m only using this for AirPlay (using Shairport on Raspbian - all up to date, etc.). The sound card model is the C-Media CM108.

Have you got any solutions? Or alternative configurations?

Thanks,
Dan

User avatar
adafruit_support_rick
 
Posts: 35092
Joined: Tue Mar 15, 2011 11:42 am

Re: USB Audio Adapter - crackles

Post by adafruit_support_rick »

Crackling is going to have to do with the connection to the speakers/headphones. Have you got a different set of phones to try? Does jiggling/rotating the headphone jack make the crackling better or worse?

User avatar
danstuart
 
Posts: 2
Joined: Fri Dec 20, 2013 11:39 am

Re: USB Audio Adapter - crackles

Post by danstuart »

I have. There is definitely an issue with the unit.
I have however found a workaround, and that was to reduce the USB speed down to 1.1, by adding

Code: Select all

dwc_otg.speed=1
to the boot/cmdline.txt

Whilst it does now work. I can't help but feel I've castrated my Pi! I'm now a bit limited with other USB devices I can use. Not to mention network speeds.

If anyone has a better solution, it'd be appreciated!

adafruit
 
Posts: 12151
Joined: Thu Apr 06, 2006 4:21 pm

Re: USB Audio Adapter - crackles

Post by adafruit »

we never got crackling, but we also don't have any more CM108's in stock, only CM109's which require a firmware update

User avatar
adafruit_support_rick
 
Posts: 35092
Joined: Tue Mar 15, 2011 11:42 am

Re: USB Audio Adapter - crackles

Post by adafruit_support_rick »

We can refund the adapter. Please email [email protected] with a link to this thread.

schamp
 
Posts: 9
Joined: Mon Jul 05, 2010 7:41 pm

Re: USB Audio Adapter - crackles

Post by schamp »

I had a similar problem with my CM-headphone version, and changing the USB speed as you suggested seemed to help. Maybe consider adding a note about this to the tutorial?

User avatar
adafruit_support_mike
 
Posts: 67446
Joined: Thu Feb 11, 2010 2:51 pm

Re: USB Audio Adapter - crackles

Post by adafruit_support_mike »

Thanks for the suggestion.. I'll pass it along to the folks who take care of the Learning System.

User avatar
adafruit2
 
Posts: 22144
Joined: Fri Mar 11, 2005 7:36 pm

Re: USB Audio Adapter - crackles

Post by adafruit2 »


Locked
Forum rules
Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/

Return to “Adafruit Raspberry Pi® accessories”