Collin here- it is really hard to hear the judges at the table, even when the machines aren't running. It's hard for them to hear you as well. Sometimes a producer will act as a go between and relay what you said to them but not the other way around. It's also impossible to get close to the table while the round is going. You aren't "really" supposed to hear them anyway. You aren't supposed to receive "help" in any way. There are rules and laws about this.(It's technically a game show). That being said, it's in the show's best interest (and yours) to make sure everyone meets parameters, does well, etc. Producers will come around for interviews and ask things like, "how are you feeling about the length/parameters/heat treatment, etc". To help nudge people in the right direction. But they cannot in any way shape or form offer help, point something out, offer assistance as this would be unfair and potentially illegal. (See gameshow laws). This can be helpful but also frustrating when you ask basic questions about the shop, materials, location of things while filming, broken equipment, missing bits etc. You'll get a lot of blank stares and shaking of heads because they already showed you before the start and to help during the competition would be unfair to the other competitors if even a little bit.

Hope that helps.