What should I do when the defibrillator advises a shock, however the rhythm I see (and confirm with my partner) is PEA? Am I allowed to disarm a shock that I belive the monitor is mistakenly picking up artifact and suggesting a shock when it is unwarranted?

If I am certified in manual defibrillation, however in a cardiac arrest call am not confident in my rhythm analysis, can I switch to SAED to help interpret/treat the patient?