Humming through AUX2 record section


Went to do some recording of vinyl to tape and have a loud humming noise through AUX2 when mute is turned off on the 252 on the record button section

I’m using Supercap with Superline, 252/Supercap

Weirdly I don’t get the hum through the headphones. Just the speakers.

No humming through AUX2 when the Record section of AUX2 is muted

Any ideas?

Which inputs are your Superline/Supercap and your recorder connected to? What’s the recorder?

Nak CR5-e
I’ve disconnected the tape recorder and still get a hum when the mute is off on AUX2.
I’ve tried the Nak connected to different inputs too.

I’m using a 4 pin DIN to RCA on AUX2
Weirdly I only get the humming when both the RCA’s (L&R) are connected. If I remove 1 (doesn’t matter which) the humming stops.

Weird I don’t get a hum when the record mute is activated or when I select a different source on the record section

A DIN4 to RCA doesn’t sound right. Unless you Are you taking signal directly from the Supercap to your Nak? If so, you don’t want to connect from the Nak back into the 252 otherwise you’ll likely get an almighty hum from an earth loop.

You should use a tape I/c (4xRCA phono to DIN5) on a buffered record in/out.

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Sorry - don’t think I was clear.
I’m using a 5pin to RCA set for the Nak. The 4 pin to RCA is from a Superline connected Supercap to 252 AUX2 RCA input. That’s where the issue is.
Make sense ?

Ah, ok thanks.

Does it still happen if you input the signal from the Superline/Supercap to a DIN input? Using the Naim 4-5 interconnect?

Failing that, what about if the Superline is connected just via AUX2?

Interestingly I don’t get power from to the Superline when I use the SNAIC from AUX2 + Power to Superline. Hmmmmm - Something weird is going on.

I don’t have a 4 pin DIN to 5 Pin signal cable to try instead of the 4Pin DIN to RCA

How is the AUX2 socket assigned?

I changed it using program mode. There’s no power coming to Superline from AUX2 as green logo not coming on

There’s nothing else plugged into the Regular DIN AUX2 input?


Do you have the link plug fitted to the Superline?

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Ahahhhaa - good point - forgot I needed that in if using AUX2.

It’s probably in the loft so will try tomorrow !!
Will keep you posted
Thanks for the help so far.

Interestingly I’ve not used the record function since getting the Supercap (used Aux 2 previously with no drama’s).

Hopefully it’s just the cable and not the Supercap causing the issue. The humming is the same frequency as the faint transformer hum in the Supercap.

Could it be the stacking order is wrong for my right hand side rack.

It’s currently (bottom to top)

SC DR for 252
555PS Dr for NDX2
500PS for 500
SC DR for Superline

The DIN4 to RCA cable you are using. Does this cable split into L&R near the RCA end or the DIN end ?

Split is near RCA end.
Is that right ?

Ok, just curious.

Did you try using DIN to DIN (Naim 4-5 interconnect) from the Supercap to the 252?

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Morning . So, I’ve found the plug and now tried the AUX2 power straight to NAC252.

The humming has disappeared. So I guess a problem with the signal interconnect from Supercap, Burndy or the Supercap itself ……

I’ve ordered a 4Pin to 5pin interconnect to use instead of the 4Pin to RCA. Will see if that sorts the issue. Will keep you posted

Let me know if any other ideas

My suspicion would be the RCA interconnect between Supercap and NAC252. Try the 4-5 Din i/c and see how it goes.

You’re probably right. It’s a Flashback 4pin to RCA. It was given to me as a stopgap so probably overdue an upgrade considering the system !