Buzzing sound from ceiling light fixture. Can the source of the problem be the dimmer?
This is not a simple light fixture. It uses a TRANSFORMER.
Dimmers are tricky devices. While conceptually they adjust the incoming current with a variable resistance, in reality they are far more complex. The end result is that for direct use with incandescent &amp; halogen bulbs, all dimmers work well. For use with dimmer-compatible (some are, some are not) LED or fluorescent bulbs, most modern dimmers (they will specify LED compatibility, as your Lutron does), they will work well.
However, your light fixtures include a transformer. That takes the 120V power and takes it down to 12V needed by the specified bulbs. That process is most definitely not compatible with a typical dimmer. The &quot;right&quot; way to dim such lights would be to dim them after the transformer. There are lights designed to work that way, but not your standard off-the-shelf residential stuff.
Update: Your dimmer (SLV-600P) is supposed to be compatible with Magnetic Low-Voltage fixtures. So it is basically &quot;the right stuff&quot;. However, something is clearly going wrong, and my recommendations still stand, primarily because LED lighting has gotten cheaper and better (more reliable, better color) over the last several years and will save a lot in energy costs.
End result: Your dimmer is modern and fine. Your bulbs are &quot;plain&quot; and, in and of themselves, likely dimmer compatible. But your fixtures are not dimmer compatible.
Options:
1 - Replace the dimmer with an ordinary ($1 - $3) switch. No dimming. No buzzing.
2 - Replace the fixtures with your choice of:

Ordinary &quot;cans&quot; that will accept ordinary light bulbs and install dimmer-compatible LED lights.
Fixtures with integrated dimmer-compatible LED lights.