Mojo 2 DSD64 DoP clips

Audio Gear Talk Chord
1

Hi there,

I’ve updated my Mojo to the v.2 “4.4” and run into a rather strange issue: whenever I play DSD64 files over DoP (through ALSA), I get random pops during playback, especially when the DAC is cold. This is not due to the USB cable as it also happens through my Poly.

I’ve done some testing and apparently this issue disappears when I upsample DSD64 to DSD256 in Roon. This is rather counter-intuitive to me since a bigger frequency on the DAC should entail more problems of that kind. What would this suggest to you?

2

Just convert DSD to PCM in Roon. The Mojo doesn’t play native DSD, and converts DSD to PCM anyway.

This is true for all Chord DACs except Dave.

3

Thanks for your reply.

Yeah I know that but 1) I like the white LED feedback and 2) I somehow prefer the conversion made by the DAC. It’s a tad wider to my ears.

4

Having a Mojo2 and Poly and having used the Mojo2 with various endpoints, your experience suggests your Mojo2 may have a fault.

I’ve never heard any such pops when playing DoP.

IMG_5591
IMG_55911920×2560 1.27 MB

Currently testing from my FiiO R7 > USB C > Mojo2

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Are you using the USB-C port or Micro USB?

5

Yes the idea of having a faulty component crossed my mind. The problem is that there’re so many variables in what may cause those pops (ALSA? CPU?) that it’s hard to tell my reseller I’m sure the device is not working as it should.

I tried both USB entries. The DAC is in desktop mode and powered by an Ifi iPower2 5V converter.

Note that you are also processing the signal before sending it to the Mojo (as in my current workaround).

6

Yes, as @mjw mentions, the Mojo2 doesn’t support native DSD, so the DoP is needed.

I have tested my Mojo2 with three endpoints and none produce what you describe.

Are you testing with the same album or did you have more DSD64 albums?

7

If you’re using the network to transport the data to the endpoint connected to the Mojo2, this will likely not be an issue.

If I connect my server directly to my Mojo2 (or any DAC) I hear the interference from its noisy power brick. Across the network and there’s no issue.

8

The issue appears with all my DSD64 tracks.

I don’t have an extra endpoint; the Mojo is connected to my Linux PC which hosts the server.

It can play without issues for 30-40min and suddenly it pops. I’m unfortunately the kind of audio autist who cannot stand those types of random alterations of the stream. The thing is why upsampling would solve the problem? Does it stabilize the buffer? Does it put less stress on the DAC conversion?

9

Just noticed, you have the 4.4 version.

I’d reach out to Chord support. They are really helpful.

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