My AEG induction stove has short enough pulse cycles it's not noticeable - a low setting just means low heat. In fact, it's the best stove I've ever used by far - it can go from gently melting chocolate to way too much heat in about 2s. Apart from boiling water I never use the most powerful settings because they'll burn stuff. The only thing it can't do better than gas is wok cooking - the curved sides don't get hot.

My parents have a different brand induction which does seem to have longer pulse cycles - maybe one every 5s or so. That is probably the effect you're describing - it'll go from essentially off to too hot and back. It's obviously a manufacture specific thing.