HifiMan HM-801 Coax DAC oddness, please advise (MacBook Pro)

Just recently purchased HM-801 and am really enjoying it.

On occasion, I'd like to use as a DAC with my MacBook Pro (Coax not USB).

I purchased this converter:

http://www.m-audio.com/products/en_us/CO2.html

I've tried several different toslink cables with a mini-optical adapter to my MBP.

With 24/96 Flac files playing with Vox or Audirvana I get some clicks and pops, but no sound.  

If I change the output to 24/48 I get audio.

If I run 24/96 via toslink out of my MBP into my Denon DVD-5000, then 24/96 via toslink from the Denon to the M-Audio converter, and finally into the HM-801 it seems to work perfectly.

I just don't understand why it won't work with the Denon out of the loop.

I'm doing more testing, but any insight would be greatly appreciated.

You are mistaken.  I am well aware that the HM-801 does not support optical.

Perhaps I didn't make this clear enough.

I am using this device to convert optical to coax:

http://www.m-audio.com/products/en_us/CO2.html

No problem, thanks for the reply.

It looks like something is wrong with the optical out on my MacBook Pro.

I copied a single 24/96 Flac file along with Vox to a thumbdrive and tried the following config on a different MacBook Pro:

MBP/Vox 24/96 -> M-Audio Converter -> HM-801

This works just fine on the other MBP where as my MBP does not work in that configuration unless I change the output in MIDI Audio Setup to 24/48.  See attached photos.

Yes, it is 24/96 via coax, but 16/48 as a USB DAC.

I can confirm 24/96 works when I chain like this:

MBP/Vox 24/96 Toslink -> Denon DVD-5000 24/96 Toslink -> M-Audio Converter Coax -> HM-801

The Denon recognizes a 24/96 signal from MBP, but without the Denon in the loop I get clicks/pops, but no music.

It appears I have either a software or hardware failure in my MBP optical output.

Probably the best choice would be to return the M-audio and look for a USB to Coax solution.

The M2Tech HiFace seems to have good reviews.  Can anyone confirm it works with MBP?

http://www.m2tech.biz/hiFace.asp

This one looks intriguing, but I can't find any reviews:

http://www.audiophileproducts.com/bravo

Any thoughts?

You have to specifically set the output to 24/96, but the MBP does support it.

I've confirmed that it works on another MBP so it looks like my MBP is FUBAR.  I'd love to replace it with one of the newly released ones.  Fast.