272 issue/mystery/concern

Posted by: DrMark on 12 October 2017

I will try to give the pertinent facts here as succinctly as possible, and my hope is that is is a setting that can be tweeked but now I am concerned.

I had a while ago purchased a crummy little Blu-Ray DVD player (Sony) just for DVD replay. Connected to the 272 via digital coax, and to my TV via HDMI. When watching a movie, after a time (10-20 minutes) a horrible static electrical crackling was coming out of my speakers. The static can be controlled by the volume control, and of course switching to a different input caused it to cease immediately.

I thought perhaps it was a function of the really crummy digital coax cable I had purchased, so I ordered a better one - nothing top shelf, but decidedly superior to what I had, which was bottom of the barrel.

Used the new digital coax - put on a BR movie. Watched perhaps half hour with no issue at all, and then the static crackling started again. I switched the 272 off, and watched the rest of the movie using my TV sound, which produces no static at all.

So obviously it is the shite BR-DVD player from Costco. So I purchased an Oppo BR-DVD player second hand. It arrived today, and you can tell the prior owner is a guy who clearly takes excellent care of his stuff - clean as a whistle.

Remove the Sony, replace it with the Oppo, and put in a CD as the first test of the functionality of the new unit. It plays the CD for about 10 or so minutes, and (drum roll please) the crackly static is back.

Any ideas short of sending it for a service? (Which of course will be costly and mean no main system music for a good while.) The noise is never present on any other input. (which is limited to iRadio and UPnP in my situation). But it is a real bummer.

Oh and last point is I have switched the digital coax from Digital 4 to Digital 3 - same delay (about 10 or so minutes) and static begins.

Posted on: 15 October 2017 by Huge

james n posted:
DrMark posted:
Sorry Richard, in my haste to post before leaving I typed the wrong thing
The HDMI goes from the DVD to the TV. (This was what I disconnected.) The digital coax goes from the DVD player to the 272. The only way the TV plays through the Naim system is with DVD; picture (and sound obviously) going to the TV from the DVD player. And the audio simultaneously going from DVD player to the 272.
Hmm - shouldn't be an issue as the coax inputs on the 272 are galvanically isolated so earth currents looking for a route via the 272 shouldn't find it. Have you tried optical instead of coax yet ?

They can still provide a route for stray fields to enter the box and interfere with the system.

Posted on: 15 October 2017 by james n

Huge posted:
james n posted:
DrMark posted:
Sorry Richard, in my haste to post before leaving I typed the wrong thing
The HDMI goes from the DVD to the TV. (This was what I disconnected.) The digital coax goes from the DVD player to the 272. The only way the TV plays through the Naim system is with DVD; picture (and sound obviously) going to the TV from the DVD player. And the audio simultaneously going from DVD player to the 272.
Hmm - shouldn't be an issue as the coax inputs on the 272 are galvanically isolated so earth currents looking for a route via the 272 shouldn't find it. Have you tried optical instead of coax yet ?
They can still provide a route for stray fields to enter the box and interfere with the system.

Good point Huge - high frequency noise further up could still couple. I always use optical when connecting digitally to anything AV wise, Just avoids any issues.

Posted on: 15 October 2017 by DrMark

There are no other physical connections to the 272 (save for the Burndy and 250 DR of course), and the NAS via wireless router.

As mentioned above, I had considered trying analog audio from the Oppo to the 272, or as just suggested I may try to see of I have or can get an optical cable.

Posted on: 15 October 2017 by james n

Thanks Mark - just wanted to check. Try optical.

James