When we were down in June there was very little night life or live music.
Was it due to off-season or is that the norm.
Just like to kick back and enjoy a few in a bar.

I'd say it's the norm. Bonaire is certainly not known as a hot spot for nightlife. There is some in town but it's limited.

There is always more action (for here, which might not look like any action at all if you're from a city), at the end of the month, when people get paid, or around holidays/special events/local school vacations. For example, the 2008 Heineken Jazz festival is the 4th weekend of May (May has 5 weekends this yr).

Most workers get paid once a month, at the end, so that's when more bands are scheduled to play at Karel's Beach Bar, City Cafe, Little Havana, etc., all within a few blocks of each other downtown. But be warned, almost all night-life is late--11pm+. If you're looking for nightlife before that, you have to hit the hotel manager-parties or happy hours (usually between 5-7pm). And some restaurants have scheduled live music during dinner hours-check the local ads (like the "Update" brochure) when you arrive.