I had a similar problem with Hutchinson lightweight tubes. I bought two and both of them had moer than one tiny, tiny leak and I gave up on them. I do not believe it was caused by the tire or debris because the replacement tires were equally light (see below) and I haven't had one problem in about 1,000 miles with them.

I switched from cheapest, heavy tubes to the Performance/Forte lightweight tubes (not the lunar light, just regular light ones). The weight went from 130 gm each (260 pr) to about 70 gm each (140), that's 1/4 lb. I have seen absolutely no difference in punctures with the light weight tubes, except the hutchinson above. I am of the camp that the tubes have little or nothing to do with flats - anything that punctures the tire will puncture the tube whether it's light or heavy.

So I can recommend those tubes. One other nice thing about the lightweight tubes (actually a really nice benefit to me) is that they are so compact when they are folded up. Take up very little space in the under saddle bag, so you can carry a tiny saddle bag. I can fit two where I could fit only one before, although I generally only carry one.