I don't know if it's normal, but the noise and ground loops of the charger have been well documented. If your DAC does not already include a USB galvanic isolator, it's a good idea to use one. They can be cheap, like $30
Does my laptop need to be grounded when charging?
I generally leave my MacBook Pro attached to its charger while listening to music files played thru my dac via USB. I have noticed that when I am barefoot and gently rub my finger over the metal surfaces of the laptop that I feel a slight fuzziness as if there is stray voltage going through me. It is not a shock per se and the sensation goes away when the charger is unplugged. The charger does not have a ground prong. Should I ground the metal cover of the laptop? Should I get into the habit of disconnecting the charger when I listen to music files from the laptop? Is this normal?
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som engineers are thinking that the USB issues are lack of a clock signal wire, and noise on the data wires noise from a charger might affect the latter, but just try it both ways (blinded) on some very clear passages or get a DAC or other 'boxes' that can reduce these putative problems... do you have a re-clocker? (I think the regenerator function in the uptone items may be a reclocker) AND... a used Apple TV3 costs ~~$40 - can then use Airplay for your Redbook data and beam it over WiFi jc is giving you a very old and very valuable tip |
I have noticed that when I am barefoot and gently rub my finger over the metal surfaces of the laptop that I feel a slight fuzziness as if there is stray voltage going through me. It is not a shock per se and the sensation goes away when the charger is unplugged.I assume the floor is bare concrete or maybe some type of conductive tile. Concrete is conductive. Especially when poured on grade, earth. I believe what you are experiencing is a very low level electrical shock. Your body may be sensitive to low levels of electrical current passing through it. Just a guess a difference of potential exists between the laptop and the concrete floor. I would suggest you wear slippers on your feet or some other type of insulator |
Cheapest: unplug it and see Best advice: post on www.computeraudiophile.com jea48 has the likely issue but could static buildup possibly affect your SQ? no matter as USB can be a very problematic interface and it appears that not all problems are known in a mechanistic sense Something to do before going any further: Call Uptone and see what they think; John Swenson (the engineer there) just moved and is likely very busy, but he is also very helpful & they have a loyal fan base No affiliation, not a customer, YMMV, my bits are shot on a closed course by a professional driver so Do not attempt |