Pro Tools 11

The pedal is a Source Audio Collider.

I have RME outputs 5/6 going to the pedal stereo inputs.

I have the pedal's stereo inputs going to RME inputs 5/6

Yes, I listen in the headphones. I can hear the guitar in the headphones.

I'm also a guitarist and use a UFX III like yours, with two vintage effects units connected.

Don't be intimidated by TotalMix FX—it’s a powerful mixer. The key is to understand that it operates differently from a standard mixing console. Each hardware output has its own independent routing (a “submix”), which is why it’s called Submix Mode.

The easiest way to work in TM FX is the mixer view (M), matrix view is too special for the beginning. Although it is the default, check the blue field at the top right to confirm that Submix Mode is activated. If it is, great—keep it this way.

Audio flow / routing

Audio from inputs is recorded unchanged in RME/TotalMix, similar to other recording interfaces you may be familiar with.

For output signals, however, each output’s routing must be set individually.
The process is straightforward:

1. Select a hardware output in Submix Mode.
    The routing for this output appears based on the fader positions for:
    -  Hardware inputs (audio from inputs) and
    -  Software playbacks (audio from the PC/application)
2. Adjust the faders for hardware inputs and software playbacks to determine which signals should route to the selected output.

Latency

Routing audio from hardware inputs has nearly zero latency, as it occurs directly on the recording interface.
Routing from software playbacks (e.g., audio from the PC/DAW) may have minimal latency, depending on the buffer size.

In your case, to route the guitar signal to output AN 5/6:

1. Select the hardware output AN 5/6.
2. Identify the source of the guitar signal:
    - either from a hardware input (usually from a mic or instrument input) or
    - from the DAW. In this case, route it to an individual output in the DAW, which will then appear in TM FX in the middle row (“SW playbacks”).
3. Raise the fader of guitar signal to 0 dB for submix AN 5/6.
4. Lower all other faders to prevent other audio from routing to AN 5/6.

Additional tips:

a) Use the “Sub” button under “Layout Presets” on the right side to display only the channels routing audio to the selected submix hardware output AN 5/6. This feature is particularly helpful with the UFX III’s many channels.

b) When working in submix mode, selecting a hardware output makes the top and middle row faders display the name of the selected hardware output or submix. This shows that routing is configured specifically for that chosen hardware output.

For further details

See this sticky post: https://forum.rme-audio.de/viewtopic.php?id=34394, which includes links to concise RME tutorial videos covering almost every aspect of TotalMix FX.

Thanks thats very kind.
Of course it is not needed the forum is for free.
I never go to Starbucks but I would probably try out once a have coupon.

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