Hi Rob,
yeah…it doesnt look like you really have very many dimples at all, let alone uniform coverage of dimples…
i tried to get a good pic off my computer screen of the uniform dimple sample…
I fear you may need a new unit, like me…
i do not think your “thingeys” are firing properly…
Here is an interesting link on the “thingeys” 
our model looks like * Frequency: 50/60Hz *, but i do not find it’s ultrasonic frequency or watts…on a different unit that was 60Hz had an ultrasonic frequency of 37kHz…)
here is a written expanation with video at the end:
julie