I have received my Pulse Xfi for a week and have been listening to it with great pleasure.
However I found a very annoying high frequency noise when playing high res audio, such as 24/192, DSD64 or DSD128.
It is a very small volume high freq sine wave like 8KHz or higher. Pausing the audio in iTunes won't help but you have to stop the DAC in Geek Perfect.
Try playing some 16/44.1 music will also stop the high freq sound.
Originally I thought it might be my power / grounding setup, but after I found the pattern to reproduce the problem, I suspect could it be of some firmware issue... any idea?
My audio setup:
MacBook Air 2012
Geek Pulse Xfi, FTM mode, XLR line-out
Geek LPS (240V)
Accuphase E-450 Integrated Amp
ProAc D15 speakers bi-wired
Thank you for quick response to my problem. :)
Anyway I found the high freq noise source and fixed a couple of hours ago.
End up it was caused by some grounding issue between my integrated amp (Accuphase E-450) and the external Pre-Out (i.e. the external direct input to power amp section, bypassing the pre-amp section), and the Pulse Xfi.
I have another AV amp (Onkyo TX-SR705) which I share the front main speaker with the E-450 by feeding the TX-705 front L/R line-out to E-450 Pre-Out input, so that I can use the E-450 to drive the front speaker while TX-705 can do its 5.1 surround sound with the centre and rear speakers.
To make long story short, once I disconnected the connection between TX-705 and E-450, the high freq noise was gone even when DSD128 was being played.
I don't know why Pulse Xfi will "leak" high freq noise when DSD files are being played when the grounding is wrong, but at least now I fixed the problem and pretty satisfied with the result. :)