I only ever bother with same-day alarms (usually within an hour or two) in which case I do turn the volume up temporarily.

On my Android phone, the alarm sounds even if I have the phone set to "silent". If there is a way to actually silence the phone, I'd love to know about it.

I'm very curious about how you end up with alarms configured that you don't want to go off, especially often enough for this to be a regular problem for you.