I was playing music using the iTunes player on my Macbook Pro. I use a Teac HA-P50 DAC conected with an optical cable as my headphones are impossible for the Macbook to drive effectively (they have a 600ohm impedance).
I was getting audible distortion on most pieces I was playing. They were from CDs I'd ripped using iTunes lossless conversion.
After a lot of playing around, I swapped the optical connection and fed the DAC using a USB output. This improved things noticeably but I was still getting distortion.
I thought it might be my headphones finally dying, as they're neary thirty years old, but turning the volume down really low, the distortion was still audible in exactly the same bits of music.
I then tried new source material and bought a 24bit 48kHz FLAC remastered version of one of the CDs I already had. I couldn't play this with iTunes so I downloaded TEAC's high resolution audio player app. The disortion completely vanished. Not a hint of it. I then played the standard CD tracks which had caused problems earlier, and they had no distortion either.
It's the iTunes app itself (12.3.3.17 - the latest version on El Capitan) that actually causes the distortion.
Grrr!
Sarah
--
If I can't drink my bowl of coffee three times daily, then in my torment, I will shrivel up like a piece of roast goat
Spiders on coffee - Badass spiders on drugs
--
If I can't drink my bowl of coffee three times daily, then in my torment, I will shrivel up like a piece of roast goat
Spiders on coffee - Badass spiders on drugs