Hmmm. Actually I've had poor auctions, in the last couple weeks, but my store is going strong.
Have been on Ebay for 6 years now, my recollection is that September is usually slow.
I do the same thing as zarzuella, I really only use auctions to get people to buy stuff from the store then, or later. I get a good number of repeat customers.
The other thing I think is important is that advice you read in these threads really is only good in the "domain" the person is selling in. I'm a stamp guy, so my experience is with stamp collectors and related categories.
MTBCards for example seems to be selling Yugioh cards - current slowness could be that the market is slow for those cards, could be that a lot of other people are selling similar cards etc.
I have noticed that what other people say works for them in their categories does not work for me. As an example, a lot of people like Sundays to have their auctions end. Sunday for me is my 4th choice. It cost me a lot of $$$ and time to figure out the best times for my category so that's all I'm going to say, but as I mentioned above, what is good in the stamp category is probably not as good in other categories.
Another odd and interesting to me, thing I've noticed is that sales of particular things go in cycles. As an example I sell Japan stamps in the store. All of the sudden I'll sell a whole pile to different people, then it goes back to very few for a few months, then another surge comes in. I have no idea why or what causes it. I've suspected that others dump a bunch of similar stuff in, get frustrated or run out and then mine look good again but that's my best guess so far.
My personal view is that there are buyer cycles, caused by a variety of things, at least in my category. Similar cycles probably exist in other categories, but for different reasons.
Anyway there's some thoughts.