Strange values (pressure, altitude)

Hello all!

I'm sending data from my PWS to WU. I have verified that displayed values in this page are correct and coherent. All the data I push are correctly stored and displayed...

Now I'm using a GET on http://api.wunderground.com/api/xxxxxxxxxxx/conditions/lang:EN/pws:1/bestfct:0/q/pws:INORDPAS92.json to retrieve these values. And it's now strange things appears:

1 - Pressure
The value in response to the GET is not the value I send. Now, for example, I'm sending 1009.3 hPa, the page of my station display 1009.3 hPa  but the GET answer is 1012 hPa  !

So my questions are, what is this 1012 hPa value and how can I query (and obtain) the true value I send ?

2 - Elevation
In the GET answer I have to values : 

• elevation in display_location which indicates 44.0000000
• elevation in observation_location which indicates 184 ft

The elevation I'm sending is 56 meters (which is approx. 184 ft). So what is the elevation value in display_location ?

Thanks in advance for your answers.
Pierre