ASIair Plus and AP mount set longitude command


Any seen this?
When I connect my ASIair Plus to my AP 900 CP3 the ASIair Plus sets the latitude and longitude among other things.

I have noticed the value it set for longitude is not a valid value but everything still works.The Longitude on my ASIair is set to West 76° 55' 33".
The command that is sent to the mount is :Sg 436*55:33#. 

It should be :Sg +76*55:33# (this is what the AP ASCOM driver sends also)
Slews to objects with the ASIair Plus work fine.

The :Sg command documentation that I have only says the format is DDD*MM:SS but does not state what is a valid DDD.