Thanks for all the thoughts and replies. I have so little faith in flooring companies I've decided to just live with it.

Rocks,

it seems unlikely your problems is going to equalize as it keeps reoccuring and in different spots.

so my guess is the floor was not accurately assessed and prepared initially.

the moisture barrier , if used, is not working.

my thoughts are you are only going to correct it by removing your floor.

Since it is a reoccuring problem and not something that happened right away, my diagnosis is probably off as that would eventually stabilize..but not if it is continuing to get wet.

is there ground water?
what are the water tables for the AREA?
maybe you are reaching high levels in the winter..

any rains? what is your region?

Thanks for the reply James,

You said: my guess is the floor was not accurately assessed and prepared initially.

I would have to agree, his method of determining moisture content was apparently hokum. Being that he disappeared from the face of the earth within months of installing the floor, I dont have a lot lot of confidence in his work. I had him out within six months of putting the floor down because it was cupping, and he told me we could rip it up and seal the slab but that there were problems with doing that as well, and I told him lets just see what happens. Well I could never reach him again.

You said: the moisture barrier , if used, is not working.

From what I gather his method of laying thick plastic down, then plywood, then shooting the plywood down with 20 nails a sheet eliminates the effectiveness of the moisture barrier.

You said: is there ground water?
what are the water tables for the AREA?
maybe you are reaching high levels in the winter..

any rains? what is your region?

I cant find good info on the water table for my area of North Texas (The city is Garland, a suburb of Dallas) but I do know that we have been in a significant drought for a couple of years. Although I cant get specific information on how low or high the water table is, everything I Google indicates that because of the drought the water tables everywhere in this area are falling, dramatically.
Two summers ago we had such a bad drought that a record numbers of trees died all across Texas from a lack of water, nearly every county in Texas had wildfires (I happen to know because I'm a fireman) because of the dry conditions.

Rain? Not much. I've looked at rainfall totals for the area month-to-month and nothing pops out at me. The last couple of months we've had more rainfall than usual, but in looking at the past 5 years of rainfall data periods like this are not uncommon.

If its a water issue it would have to be coming up under the slab as there is no place where the grading around my house comes up to the slab, nowhere near it.

I would like to find someone who could come out and tell me what the moisture content is of various areas, preferably by non-destructive testing (I had a company come out, the kid in training it looked like, I'm not sure he was even shaving yet, and he drove a probe (nail) into my floor at a seam and took a measurement where the floor was cupping last year, he got the reading, shrugged his shoulders and said "eeh, not too bad" then proceeded to tell me that maybe nothing needs to be done, that he's "seen these things go back to normal before"...which it did, but his diagnoses didnt really tell me much. Not to mention that he couldnt get his probe out of my floor, I had to wrestle it out with pliers)

I had not monitored the RH in my home and now that I have I can tell you that it was remarkably low about the time that this started again this winter. I have taken the advice of others on this site and purchased a humidifier so hopefully that will help, though I understand it will take quite some time. I Probably wont know the effectiveness until next year when I run the humidifier to prevent such dry conditions, we'll see then.

My wife is sick to death of the entire subject. I feel though that if I'm gonna pay tens of thousands of dollars for a floor it shouldnt be nearly this frustrating.

Low humidity is a definite possibility! Go to http://www.weather.com/outdoors/home-im ... t/humidity reading right now for Dallas Tx are 53 degrees outside, 35% Relative Humidity, 74 thermostat setting inside produces 17% indoor relative humidity too low. Stephen is correct you most likely have a moisture imbalance. I am an NWFA inspector in El Paso and see it all the time. I use a Lignomat Versa Tec moisture meter which scans, pin, and insuti testing. Utilizing the pin meter with insulated 1 1/2" pins I would read mc top 1/4" and record the reading, drive pins to bottom @ 3/4" and record reading. If the difference 1% or more cupping may occur. Cupping of 0.10 is consider acceptable 0.02 not so much. Needs remediation.
Driving into the plywood will usually produce a higher reading and that will generally define the imbalance. Need further proof remove a board and insert an insuti probe with will tell you what the relative humidity at 40% of the slab is if 75% or more definitely moisture from the slab. Cupping from moisture generally is U shaped edges higher than the center. Dry cupping generally has High edges but but drops down and the center is flatter with checks generally occurring evident. Obviously if the moisture content from top to bottom is less than 1% is probably is not moisture related. But if dry cupping would be prominent in more than one local. This method of testing should definitively produce the real culprit. Oh and by the way there is no such thing as a vapor barrier only a vapor retarder. The best methods only produce a 95% stoppage. Additionally the retarder between the plywood and hardwood has to allow some vapor to pass or eventually the subfloor would rot. While there are numerous causes for one I found a ac drain broken, water slid down the wall and was absorbed into the slab caused a localized buckling 3 feet from the wall.
Someone with the proper equipment and knowledge should be able to assess and figure this out. Try http://www.nwfacp.org for nwfa inspectors in your area. Make sure they have the capability and equipment by asking if they can accomplish what is written here. Testing and applying industry standards should define your problem and how to re-mediate it.