Hello I have problem to get my TEAC 701N working properly with Roon. I’m using the SOtM 2000 as player and server. The teac is connected via USB. The TEAC play 44.1/16 material but any other material is either silent or digital distortion. I have been in contact with SOtM support and found out that the hardware is not a problem. I works fine with Qobus connect via usb connection from SOtM 2000 hardware.
Also tried convulsion filter (44.1/16) and this doesn’t work, no sound. I have previously used the Marantz SA10 and with this DAC/CD it works.
So my conclusion together with SOtM is that there is a software issue between TEAC UD 701BN and Roon when initializing new material via USB. TEAC have a special procedure as far as I understand.
Please look into this matter? I really appreciate your support to get this to work.
//Andreas
Describe your network setup
No problem with network. Only related to sync via usb connection. Network 1000Mbit in. Unify router, switch.
Thank you for reaching out and providing detailed information.
The core of the issue appears to be USB format compatibility between the Roon software (via ALSA on your SOtM 2000) and the TEAC UD-701N:
Roon sends 24-bit audio in a 3-byte (S24_3LE) format, which is technically standard but not accepted by all DACs.
TEAC’s USB interface expects 24-bit data inside a 4-byte (S32_LE) frame.
This mismatch causes either silence or digital noise when playing hi-res content (e.g. 24/96, 24/192, DSD).
This does not happen with 44.1/16 material, which uses a simpler format (S16_LE) that TEAC handles correctly.
Please try the following steps to improve compatibility:
Update TEAC Firmware
Make sure your UD-701N is running the latest firmware (version 1.51 or later). TEAC has improved USB Audio 2.0 handling in this version.
Force Roon to Output 32-bit Format
Go to Device Setup for your DAC in Roon and:
Under Advanced Settings, enable “Send stereo/mono content as 32-bit”.
Alternatively, enable Volume Leveling or Headroom Management in DSP settings — this forces Roon to up-convert the stream to 32-bit float, which then gets packed as S32_LE.
Add Resync Delay
Set Resync Delay to 500–2000 ms under Device Setup. This gives the DAC time to detect and switch formats properly.
Try Using TEAC as Roon Ready
As a workaround, connect your TEAC over Ethernet instead of USB and enable Roon Ready mode. This is the way we guarantee that everything will work properly.
Optional: Use PCM to DSD Conversion
You can also convert PCM to DSD using Roon’s DSP engine. TEAC accepts DoP and native DSD formats without issue.
Please let us know if these steps help, or if you’d like assistance applying them.
Everything works with a Roon Nucleus hardware. USB to Teac works perfectly with the USB port from this unit. The problem is when I use the client integrated in SMS 2000. I also have the older SMS 200 from SOtM, same result. As far as I understood May from SOtM, they will contact you in this matter when they have a special designed hardware.
I have updated System firmware to V1.60
USB Firmware V 0002051a
Both is the latest from Teac home page.
Roon ready via ethernet works perfect.
Also, Qobus Connect via USB works perfect from the SOtM SMS 2000.
I will investigate the other settings at let you know result.
I Have double checker firmware versions, and it’s the latest in accordance with Teac home page. USB: V 0002051a FW: V1.60
I only have "Max bits per sample (PCM) in advanced settings ->32bit See screen shot.
Volume is tested with fixed, variable, no difference. Activated Head room management, sound stopped (playing 44,1/16 via usb).
Resync delay tested from 500 - 2000mS no difference. see screens shot
Teac as a roon ready works perfect, no problem at all.
I have tested Native, DoP, DSD and convert to PCM. DAC and SOtM stops communicating and needs to be restarted when using DoP and native. see screens shot
Summary:
Only 44,1/16 works with convert to PCM via USB.
I have added screenshot from DAC page in SOtM, if it gives you more information.
Teac works with Roon Nucleus Rev.B via USB for your information.
Since this issue only happens with the SOtM involved, I would check further in that direction. There should be a web interface for the SOtM, is there any mention of sample rates accepted there?
When we run Roon on our Eunhasu server and play 44.1kHz/16bit audio files, the screen looks like the following.
The upper image is when playing a local file, and the lower image is when playing via TIDAL.
In both cases, the signal is passed through directly as Roon Advanced Audio Transport without any conversion.
This test was done using a Teac UD-503 DAC.
It seems the issue lies in some kind of format change in the middle, so it’s worth checking the DSP settings or anything that might alter the signal path.
Also, when we look at the DAC information, it shows that this DAC supports S24_3LE as the highest bit depth.
That means in the audio settings, it would be more appropriate to set the bit depth to 24-bit instead of 32-bit.
I Have double checker firmware versions, and it’s the latest in accordance with Teac home page. USB: V 0002051a FW: V1.60
I only have "Max bits per sample (PCM) in advanced settings ->32bit See screen shot.
Volume is tested with fixed, variable, no difference. Activated Head room management, sound stopped (playing 44,1/16 via usb).
Resync delay tested from 500 - 2000mS no difference. see screens shot
Teac as a roon ready works perfect, no problem at all.
I have tested Native, DoP, DSD and convert to PCM. DAC and SOtM stops communicating and needs to be restarted when using DoP and native. see screens shot
Summary:
Only 44,1/16 works with convert to PCM via USB.
I have added screenshot from DAC page in SOtM, if it gives you more information.
Teac works with Roon Nucleus Rev.B via USB for your information.
Please test playback of 88.2kHz/16bit and 176.4kHz/24bit audio files.
We need to check whether the issue is related to the 48kHz family of sample rates or specific to 16b/24bit format.
88.2/16 works fine. Se picture of signal path and display of teac. I also activated convolution filter with same track, does not work. Teac shows DSD2.8 wit convolution filter active.
176.4/24 does not work. Se pictures,teac show DSD5.6. Tested same track also with convolution filter, same result, not working.
Thanks for those tests. So it sounds like multiple types of 16-bit content works as expected, but 24-bit does not. Have you by any chance tried a factory reset on the SOtM unit yet?
Before the sms2000 I had the SOtM sms200. I have the same problem on both units.
Previous I used the roon nocelus revB as server and sms200 as client.
Before switching to sotm sms2000 I tried usb directly from the nocelus to the teac. And it works with all formats. So I have not tested a factory reset.
I will try som other tests with DLNA configuration from sotm.
