I've had two Dac8 Pros - the first had one noisy transformer and the Apple remote would become unresponsive after anywhere from 2 to 8 hours use. The transformer mechanical hum was not excessive (had to be next to the Dac to hear it) and was exacerbated by the oak shelf that my Dac was on, acting as a sounding board. A small circle of felt placed on top of the transformer cut the noise to acceptable levels. Interestingly, I've noticed Okto are now shipping with this felt/foam in place. Unplugging the Dac from the mains would always restore the remote's functions.
I disconnected the DAC from PC and power amp, but the remote would always become unresponsive after a period of time. Pavel agreed to send me a replacement. It has a perfectly quiet transformer (no felt circle). But the remote issue continued with the replacement unit. Having two units with this problem made me suspect something in my music room (separate from the house) was causing a problem, so I took the original unit over to the house and plugged it in there. Bingo! - the remote worked perfectly for more than 24 hours. Suspecting possible SMPS interference I moved all my gear with SMPS (except the class D power amp and the fanless PC) to the house and plugged it into the same socket as the Dac. No problems, the Dac remote continued to work fine.
So then I took the Dac back to my music room and placed it about 2 feet to the left of the main rack. The remote continued to work fine, but the replacement Dac which was in my rack on a shelf about 6 inches above the power amp would continually become unresponsive to the remote whether the rest of the gear was on or not.
Suspecting the power amp was causing the problem I turned it off at the standby switches and left everything else on overnight. Lo and behold, both Dacs were responding to the remote in the morning. My Dac 8 Pro is now on the top shelf of the rack about a foot away from the power amp and has been perfectly fine for more than a month. The original Dac was shipped back to Pavel.
Given that the Dac has a case without vents I'm presuming that RF/EMI is affecting the remote sensor via the front panel. Early plasma TVs cranked out a far amount of RF and were known to interfere with Apple TV remotes. It's just a guess and perhaps others (or Pavel) with more technical knowledge can respond to my findings.
- for a switch was too great. In this day & age, when rebooting solves most problems it seems like a missed opportunity & we should have increased price. Perhaps switches mess with SINBAD's? But better measured DAC's have switches...
