Recent observations:

1) Changing the same external SSD from an OWC FireWire 800 dock via Audioquest .75m Carbon cable to a Seagate GoFlex STAE126 dock via stock white Apple cable or Elgato .5m black cable, sounds terrible.

Could this be due to the chips in the Thunderbolt cables siphoning detailed frequencies from the audio signals?

Changing back to the FW800 dock changes the sound quality back to 3 dimensional soundstage, whispy highs, tighter bass, cleaner vocals and acoustic guitars. Same SSD hard drive for both scenarios, high-res music only on the hard drive.

2) I recently upped the RAM from 8GB stock Samsung to 16GB RAM and the sound went terrible.

Does anyone know if RAM Memory has to 'burn in' like a cable or DAC?

I tried Samsung 16GB 1333mhz CL9, Crucial 16GB 1333mhz CL9, Crucial 16GB 1600mhz CL11, Corsair Vengeance 16GB 1600mhz CL10, all had roughly the same effect on the sound with slight variations.

My stock Samsung 8GB has thousands of hours of high-res music play through it and sounds much much better than the brand new 16GB sticks. 16GB RAM adds color, bloomy un-detailed bass, less defined soundstaged, less clear vocals and acoustic guitars.

Same results occur whether using stock iTunes or Pure Music's Memory Play (via RAM).

Many thanks in advance for any thoughts.

My gear includes:

Early 2011 MacBook Pro Core i7, 17" w/ Apple 512GB SSD internal HD

External SSD OCZ Vertex 4

Apogee Duet 2 USB 192k DAC, Audioquest .75m Carbon USB cable

High end separates Krell, Mark Levinson, balanced solid silver XLRs, copper ribbon speaker cable, sensitive KEF speakers

Burson Audio headamp, AKG 702 head phones