OSSC Audio not working on AV1, except with Mega Drive 1

[tdawgretrogames]

Hello,

My OSSC no longer has audio on AV1 except when using my Mega Drive 1.

I have reset settings / firmware, and it still doesn’t work. The Dreamcast (AV3) works fine.

Any thoughts on what may have happened?

[nmalinoski]

What other consoles have you tried? Does your MD SCART cable take mono audio from the back, or stereo audio from the front? Assuming you have an OSSC 1.6, do you have the audio jack next to the HDMI port configured as an audio breakout or as audio input for AV2?

[tdawgretrogames]

Hello, I have an OSSC 1.6, and I have a scart lead that integrated a phono in from the Mega Drive’s headphone port. This is plugged into the OSSC’s headphone jack.

Other systems that we’re working fine till today are a Super Famicom, N64, NESRGB, Saturn, Dreamcast (scart), PC Engine and PS2 (component). Now these do not have sound ?, but Dreamcast via VGA does.

*Edit I double checked the Mega Drive audio cable, and made sure to test systems with no switch etc attached to the OSSC

[tdawgretrogames]

Update: I unplugged the phono line in and suddenly sound was restored.

Is there a setting I’m unaware of to enable / didisable how the jacks work? And why would the functionality suddenly change? (Maybe I changed a setting by mistake?).

Glad for the fix as I’m loving my OSSC ?

[ErebusMaligan]

The audio port you are referring to is not intended to be an AV1 input. It’s supposed to be an AV1 audio output, or an AV2 audio input, which is toggled by the small switch next to it.

It will function as an input for AV1 if it is set to AV1 output and the scart audio pins are otherwise not wired up I think I remember seeing, but generally I don’t think (and someone correct me if I am wrong) it was intended for feeding input audio from a gen/md model 1 headphone jack.

[nmalinoski]

Hello, I have an OSSC 1.6, and I have a scart lead that integrated a phono in from the Mega Drive’s headphone port. This is plugged into the OSSC’s headphone jack.

Some quick clarification:
– The 3.5mm TRS jack next to the HDMI port on the OSSC isn’t intended to be an input for AV1–it’s a line-level breakout for AV1 or line-level input for AV2, depending on the state of the adjacent toggle switch.
– ‘Phono’, as I understand it, means unamplified audio from a phonograph, and a ‘phono’ input on a receiver or amplifier will apply both amplification and an RIAA curve.
– If one of these jacks is designated ‘headphone’, it is output only, never input; and it includes amplification to power headphones, rather than being line-level.

It will function as an input for AV1 if it is set to AV1 output and the scart audio pins are otherwise not wired up I think I remember seeing, but generally I don’t think (and someone correct me if I am wrong) it was intended for feeding input audio from a gen/md model 1 headphone jack.

If it functions as one, like you say, when audio is not otherwise wired up, then I would call it an unintended side effect and not any kind of functionality that should be relied upon.

Update: I unplugged the phono line in and suddenly sound was restored.

Is there a setting I’m unaware of to enable / didisable how the jacks work? And why would the functionality suddenly change? (Maybe I changed a setting by mistake?).

As ErebusMaligan mentioned above, that jack is not intended as an input for AV1. It sounds like audio was connected in the RGB cable, and that was being bridged with the audio from the MD’s headphone jack. I’m not sure exactly how that would cause no audio, but it apparently does.

If you’re okay with the mono audio from the RGB cable, I would recommend you continue to use just that RGB cable. If you want stereo, and you’re comfortable modifying the cable yourself, you can disconnect audio from the console and wire up a 3.5mm TRS lead that would connect into the headphone jack on the front; otherwise, you can get this kind of cable premade from Retro Gaming Cables (Regular version, PACKAPUNCH version).

[tdawgretrogames]

Thank you very much for your help everyone, problems solved 🙂

[evilsim]

“which is toggled by the small switch next to it.”

thanks! found this useful 🙂

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