Bit of a necro post, but I think I've figured something out. It doesn't matter how you respond (fire truck, fire alarm, house itself, alert icon, whatever), what does matter is how long the job exists before you respond. If I respond immediately, then there's at best a 50/50 chance of actually responding to the emergency. If however I wait 5 or 6 sim minutes after the emergency shows up to respond, then there's like a 90% chance of the job functioning correctly. Have no idea why this is, and EA definitely needs to adress this, but for the moment I see this as a workable (if not ideal) workaround.