Problem with AB box and Y box

Hello,
I want to plug my aeros in a quite strange way and I need help to understand why is it not working.

Here is the signal chain :
Guitare → AB box
A → looper → Y box → Amp
B → Y box → Amp

When the AB box is in the A position : no problem, it’s the normal way to use a looper. The guitar signal go to the looper, and then go to the Amp. I record a loop and it plays normally.
The Y box (between the looper and the Amp) receive only one signal from one of its inputs (from the looper). The input linked to the B of the AB box is unconnected from the guitar (because the AB box is on A position)

But when I swith to the B position, THE GUITAR LEVEL BECOME LOWER, while the LOOP level is still the same. Strange no?

And even stranger : when i add some effect pedals between the guitar and the looper, it’s not the GUITAR level that become lower but the LOOP level !!

It shouldn’t change because in the B position, the Y box receive 2 inputs : the loop previously recorded on the looper, and the direct sound of the guitar (without passing through the looper)

How can the guitar, when going directly to the Y without passing through the looper, can affect the level of the loop signal that is already recorded in the looper?

Anybody have a clue?

Thank you!

Hi Olivier,

Thank you for providing all those details! To help me understand the setup better, could you please record a short video showing the devices, the connections, and the signal chain? This would be really helpful. You can send it to support@singularsound.com, and I’ll do my best to resolve the issue for you.

Please also include this reference in your message: Problem with AB box and Y box.

Thank you!