Problema solucionado. Los de Cardo me respondieron un correo con todos los pasos detallados. Copio y pego por si a alguien le ha ocurrido lo mismo.
" Hi Oleguer,
Thank you for contacting the Cardo Systems Support Center.
Have you tried to activate the intercom using a single tap of the A button on the SRC-System or a single tap of the Q1 IC button? You can perform a full reset the Q1 and SRC-System then pair them together for intercom communication.
To reset your Q1:
Start with the headset powered on and in stand-by mode - one blue flash every 3 seconds from the LED indicator.
Press and hold the Vol + button until you receive a red/blue alternating flash.
Press and hold the Music/Mobile button until red/blue flash changes to slow purple.
Q1 will flash purple 5 times, followed by a couple red flashes before shutting itself off. Reset complete.
To reset your SRC:
Start with the headset powered on and in stand-by mode - one blue flash every 3 seconds from the LED indicators.
Press and hold the Mobile button until you receive a red/blue alternating flash. You will see the device flash red a few times like it is powering off, but keep the Mobile button held until red/blue alternating appears.
Press and hold the Vol + button until red/blue flash changes to slow purple.
SRC will flash purple 5 times, followed by a couple red flashes before shutting itself off. Reset complete.
To pair your Q1 with your SRC:
Start with both headsets powered on and in stand-by mode - one blue flash every 3 seconds from the LED indicator(s).
On the Q1, press and hold the IC button down until you receive a rapid red flash. You will see a few red flashes initially like the device is powering off, but keep the IC button down until rapid red flash reappears.
On the SRC, press and hold the 'A' button down until you receive a rapid red flash.
Watch the LED indicators on both headsets. They should both flash rapid red until the devices have found each other. At that time, both headsets will pause on a solid red light for a brief moment before returning to the slow blue flash. Make sure this occurs before continuing.
Please feel free to contact us if we can assist with any other questions.
Best Regards,"