[Dublo7]

So recently I've been noticing clipping present when listening to my computer system.
 
I run the Cantate directly through my PC/Mac via USB. I've tried different software and the result is the same. I've tried a wide range of lossless files and it still happens every now and then - it doesn't repeatedly happen in the same places in the songs, so it's lead me to believe it's either a volume/sound setup related problem or a hardware problem.
I'm trying to fix this on MacOS, so any suggestions would be greatly appreciated. Do I just have to fiddle with volume levels? Can some sort of fault with hardware cause this? Should I be changing output buffer levels (I'm using Songbird for playback of FLAC files)?
Oh, and this happens regardless of whether the files are on an external HDD or on the internal HDD. And as far as I can tell, it doesn't happen when I listen to the headphones from the headphone out, so I doubt it's a problem with my cans.
 
Thanks!

 

[MadCow]

Not familiar with Songbird, but make sure you don't have any audio processing such as EQ, volume normalization, pre-amping, etc going on, to test and rule out those possibilities.
 
Also check your Audio/MIDI settings, try setting the output's sampling rate and bit resolution to match your source files and see if it helps. You might want to try shutting down Songbird before making these settings.
 
Also try playing your FLAC files with another program, such as VLC?

 

[Dublo7]

OK, so I was just doing a bit of fiddling and I noticed that Foobar and WASAPI on my PC eliminates the clicks completely.
So... that means the problem lies with Mac OS.
 
Hmmm... Is there some sort of WASAPI equivalent on Mac OS?

 

[khaos974]

Core Audio, iTunes uses it, I don't know know for Songbird. But switching to  iTunes requires to convert all your Flac files to ALAC.
Check out "Obtaining a bit perfect outout with iTunes" on Google to parameter everything correctly.

 

[Dublo7]

Okay, so I've been using iTunes with ALAC files and the clicking is still occurring 

 

[khaos974]

And with the digital volume control down, does it still clip?
And you could check your files with an audio editor.

 

[Dublo7]

By the digital control volume, do you mean the volume control in iTunes or in Mac OS?

 

[khaos974]

Try both.

 

[silverxxx]

The most i found on this subject is to go to :  Applications -> Utilities -> Audio MIDI Setup and change the sampling rate to max (of your dac) and 24bit . It seems 24 bit might be important. Also the volume control was an issue in itunes prior to 7.
 
Edit: i looked up your dac and the issue could be to do with it's 16 bit resolution. If the os does the volume and sampling in 24 bit, and the dac truncates that to 16 bit it might cause distortion. There is another dac with a similar problem, and that is also 16 bit. If you could find a player that supports dithering it could help solve this problem, if indeed it is caused by this. Although i would think such distortion would occur in the same places. Unless you change the volume.
 
I hope this helps.

 

[silverxxx]

Me again, ignore the second part of the last post, i think i am wrong.
 
However there could be an issue with the usb cable, try a shoter one and don't use a hub. The DAC chip PCM 2702 extracts the clock from usb, so it could be it.