then forget about QS for a while.
Sometimes the numbers are odd. Its not very common, but it did happen to me couple of times.
As long as your ctr is good, and ur cpc is fine, u are good.
Its not too hard to up ur QS: relevant kws in ur lander and in metatags, ur exact kw in ur lander couple times, links to other parts of ur site, dont try to make it like a salesletter or a thin squeeze page, add sitemap, privacy police, terms and cond, etc, as soon as u have enough clicks, get 1 lander for every fat keyword so u can optimize it even more and get better QS and conversions.
Here is a golden trick I'll provide: in order to add relevant content in ur Adwords landers to keep Google happy AND u happy, what u need is to use jquery dropdowns "expand/collapse", so the user has to click in a link to expand the div and read what it says.
Its a clever legit way to use some relevant content in ur ppc lander and at the same time avoid visitors clicking away or getting too distracted from your main purpose.
Hope it helps.