[edit: see last post, this has been fixed]
Our intercom box to communicate with the participants in the MEG shielded room is not working well. Importantly, the sound from the participant to the desk still works ok, allowing us to continue operating safely and properly monitoring the participant.
The issue is the other way, when talking to the participant. There seems to be a bad contact in the “push to talk” button, even if it is pressed firmly. This randomly drops the volume that they hear. It may sound muffled or appear to cut off, especially if they are wearing the foam ear buds.
Until a solution is found - likely replacing the system - please be aware of this and prioritize opening the door to talk to the participant face to face as much as possible. Keep intercom instructions short and let the participant know of the issue and what you will be telling them, e.g. that the recording is about to start and that they should stay still when they hear you.
Let me know if this gets worse or if it’s causing difficulties with your study.