If the headsets go down for one team the other teams are turned off till both can have them operational.
I believe that is NFL only. I think NCAA leaves it up to the individual conference to implement specific rules like that.
NCAA Football Playing Rules 1-4-12 (coaches’ phones/headsets/communication devices)ARTICLE 12. Coaches’ phones, headsets and communication devices are not subject to playing rules penalties before or during the game.
a. A conference may develop a policy to provide guidance in handling situations dealing with failure of coaches’ headsets.
b. For Division I Football Bowl Subdivision (FBS) football, within game management responsibility, each team may use a maximum of 23 headsets with guidelines as follows:
1. Fifteen (15) of the headsets may be used by countable coaches and graduate assistants for coaching purposes.
2. Three (3) “listen only” headsets may be used in the Coaches Booth by individuals who are full time undergraduate students or are within 10 years of exhaustion of eligibility or, if earlier, college graduation. Only countable coaches, graduate assistants and the three individuals using the “listen only”devices may be in the coaches’ booth. (Exception: One communication technician.)
3. Four (4) of the headsets may only be used by Squad Members or up to four designated full-time undergraduate students.
4. The one remaining headset may be used on the field for non-coaching activity.
5. Headsets that are used for medical, game operations, security, etc. staffs are exempt from these limitations, provided the communication is separate from coaching communication devices.
6. One communication technician in the team area and one communication technician in the coaches’ booth may be on the coaching headsets to monitor and handle any technical issues with the headsets outside of the allowable 23 devices.
c. For all other NCAA football programs, each team may use a maximum of 23 headsets with category limits managed at each conference’s direction.