I have the Zen Stream using a USB directly to my Denafrips DAC > Preamp. Although I have not tried internet radio, I have no lag whatsoever with Tidal, or from my hard drive server connected directly to the Stream via the USB input.
IFI Zen Stream users
I have a Zen Stream I bought about two weeks ago. I am using the dac in my Mac MA5300. I started using SPDIF when I first got the unit, then moved on to USB. Web radio often delays a minute or two before it will play. Spotify delays are much less, but can clip a second or two off the begining of songs. Delays seem shorter with SPDIF. My previous stream was a Yamaha WXC-50, and didn't exhibit any of those issues with SPDIF (USB not on that unit). Anyone else had, or having these issues? Ideas? Thank You!