Twittering n-Vi ?

Posted by: james n on 19 August 2010

I've got a strange earthing problem.

Setup - Naim XS, n-Vi, Weiss DAC202.

Weiss connected via a hi-line to the CD input of the XS.

n-Vi via a standard Naim interconnect to the AV input - unity gain selected so the n-Vi controls the volume.

The n-Vi is connected to my Virgin V+ box via Toslink and to my plasma via DVI through a Geffen HDMI switcher. The V+ box is connected via HDMI via this switcher too.

I noticed last night that when the AV input is selected and the n-Vi is on, there is a low level buzz (head close to the speaker) with a bit of 'twiterring' too when the n-Vi is doing something. If i turn the n-Vi off, the noise goes, if i select the CD input, there is no noise apart from the usual gentle hiss so music listening isn't affected.

If i do the same test again with the Weiss disconnected from the XS there is no noise. My old DAC2 joined the signal and mains grounds via a 25ohm resistor - i presume the 202 does the same (yet to measure it). The n-Vi makes the same noise whether the TV or V+ box is on.

Any thoughts ?

James

Posted on: 20 August 2010 by gone

Mine used to do exactly that when I had a Naim preamp, but now the problem's gone away. Maybe something to do with earthing topology?

Posted on: 23 August 2010 by james n

Thanks Nero - i'm sure with my old setup there was a buzz before the n-Vi powered up (i'd just set the sequence on the universal remote to keep the pre muted until the n-Vi powered to get rid of the buzz). It's nothing major just a slight annoyance and when i get the chance i'll do a bit more investigation on where else i'm getting an earth loop when AV is selected.

James

Posted on: 07 May 2011 by harpercarrer

james n, I note that you have connected your n-Vi to a Virgin V+ box using the Toslink connection. I have a Topfield PVR that I have connected to my n-Vi in the same fashion. The problem is that I cannot get a signal lock unless I conduct a factory reset of the n-Vi (which I am certainly not prepared to do each time I use it).

Three questions if I may: 1) have you encountered similar "handshake" problems to me 2) if so how did you deal with them 3) which toslink cable did you use? Kind regards Lawrence

Posted on: 09 July 2011 by james n

Hi Lawrence - are you running the latest firmware. I know mine locks up a lot quicker now than it used to since the latest firmware upgrade. I think ( and Naim should be able to confirm this) that there is a setting buried in the menus that allows the n-vi digital inputs to have a wider signal lock set if it's having trouble locking to the source. I've not had any problems where the box won't lock at all.

James

Posted on: 09 July 2011 by Richard Dane

John, there's the option to fix the sample rate within the nvi menu. This sometimes helps with poor digitl sources where the sample frequency is not rock solid and the nvi loses lock.

Posted on: 24 July 2011 by Jonas Olofsson

My n-Vi just started to hum, Im at the point where I dont have the energy anymore to do anything about it anymore, have sent it to service to many times already... What happened to the legendery Naim quality