DCC951 No audio recorded over optical input


I have a DCC 951 which has always playbacked very well. Today I tried to record something. There was already a recording on the DCC tape and I recorded something over it using the optical input.

During recording the music was coming through the DCC951 over my amplifier, so sound was going into the DCC, however when I played the tape back: nothing. So previous recording was erased, but nothing new had been recorded to the DCC.

I also tried the analog input, and a recording was made and that played fine.

What is going wrong? Recording over anlog works, but optical input just creates a blank tape.

FYI: The DCC player still has the original SMD capacitors.



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Hi and Welcome,

It could be a dirty head, or a bad felt pad in the tape.
Have you tried multiple tapes? The pads can be replaced btw. I would start with those 2, before diving deeper.

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Thanks to your youtube video’s I had already cleaned the head and felt pad. But I would have to assume that tape and head are OK as I can record fine over analog.

I have been doing further testing, digital input also records fine. Then out of curiosity I tried a different output device over optical (older CD player) to record from. And that recorded fine as well. So for some reason the output of the first device (modern USB external sound card with optical output) is playing back during recording but nothing is recorded on the tape.

Anyhow, my conclusion is that the DCC player is working fine, but for some reason some optical connections are more compatible than others?

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Ok, so analog is ok.
It might be that your USB audio card is sending the copy protection bit, but usually this would show in the display.

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Nothing is displayed Ralf. However I have now found out that when I use VLC media player over the same setup sound is being recorded. Previous unsuccessful attempts have been with Audacious software. Case closed, there must be some difference between the two software packages, but I’ll just use VLC for recording to DCC. Audacious has been fine so far for recording to other media over optical. But VLC will do as well.


I’m having similar trouble.
You have tio be extremely clear to which output your media
player is going to send data…

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This is good to know!

Also check the settings (in the audio program as well as in the control panel) and make sure it’s outputting 44.1kHz or 48kHz stereo PCM, so no multi-channel/surround, and no Dolby or DTS or other encoding.



Now this is the part where I get puzzled… if a dcc recorder gets a signal not supported by the deck it stays silent however in this case there was sound but still no recording…

Right. If the digital signal goes through the dcc730 digital input and output correctly, it means it can record it. If it gets something it can’t handle, you’ll just see “check digital in” and you can’t record. If you record a digital signal and it doesn’t play, it probably means there’s something wrong with the cassette (stick shift symptom) or with the mechanism (excessive wow/flutter). Those problems can be fixed.

=== Jac


Well checking these settings has helped me out a lot. Setting audio output to 2 channel 44.1kHz has made my USB sound card work consistently, with any audio player. Thanks for the advice!

For some reason the DCC951 is not liking my USB soundcard on two channel 48kHz (ESI U24XL). No sound on that setting, and no error to check optical in. Setting output to 16 or 24bit using 44.1kHz works consistently.

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If you set the output to 24 bits 44.1kHz and record it on the 951, it will encode 18 bits. That’s probably your best option.

No idea why the recorder wouldn’t give an error but still doesn’t record anything. Maybe the USB audio adapter sets the Validity bit wrong or something? That way the signal would still be valid 48kHz PCM SPDIF but you wouldn’t hear anything when playing back because the recorder mutes the signal while it gets (sub)frames with the validity flag set wrongly.


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