momentary stuttering before it starts to go to work

My concern is probably off-base from that of the OP, but we just replaced our unit which just suddenly failed after about, I want to say, 4- 5 years.

One day when I pushed the 30-sec. heat button, there was a loud sound that resembled an alarm clock going off, and boom, that was it. No more microwave. We switched wall plugs, waited 10 min, tried different settings, all to no avail.

Here's our CURRENT MICROWAVE ISSUE: After replacing it with a 1000 watt, really nice unit, (don't know if you can say brand names on here or not), but now when we press the 30-sec heat button, there's this momentary stuttering before it starts to go to work. It works like a dream otherwise, but 3 days later, it still does that stutter at the first press of the button. Question: IS THIS NORMAL, and we should just get used to it - or is it due to a faulty part, design flaw, or an early sign of a soon-to-be malfunctioning chip inside somewhere?

Being seniors, we'd rather not go through the process of carrying this big heavy thing back to the car, and to the store, to replace it all over again if we don't really have to.

Any info appreciated. Thanks for reading.