Planet13 - 4:49 am on Jan 3, 2012 (gmt 0)
What would be considered a "technical problem"?
Well, once I accidentally put a noindex tag on my home page. It was there for a whole month before someone else pointed it out to me. Not really good for SEO purposes...
The thing was, I had checked the code of that page probably four or five times looking for errors, and just looked right over it. Now THAT was a noob mistake...
You probably have a google webmaster tools account. You should try and use the fetch as googlebot* to see if the pages return a valid 200 response and that the code matches what the code of your web site looks like when you do a view source (this helps to check whether anyone has hacked your site).
Also, you mentioned one other thing:
I've had SEO people tell me it wasn't Panda...
1) Did those people actually LOOK at your site?
2) What DID they say the problem was?
Also, do try to search for a unique string of text. That's really going to help in terms of discovering whether it is a penalty, Panda, or possibly some other algorithm based ranking issue.
*That is one reason I miss the google cache. When looking at backlinks of my competitors, I would often see links from some pages that were unrelated. I would visit those pages in my browser and didn't see any link to my competitors on them. But if I looked at the google cache, I could see that those pages had been hacked and were serving up different content to googlebot than to standard web browsers. It's good to let a web master know when his site has been hacked - especially if it will rub out a link to a competitor.