I was able to find the parts to give a direct link from the 250 to the 990. Partsexpress has a 6' 1/8 to 1/8 plug
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=181-713&CFID=185037&CFTOKEN=95657632
and a 3.5 to 2.5 converter.
http://www.partsexpress.com/pe/pshowdetl.cfm?&DID=7&Partnumber=090-324&CFID=185037&CFTOKEN=95657632
Gonk - are you saying they are not compatible because of the size difference or because of the information output? If it is a size issue these should work...but if it is a info issue I guess they won't. Not sure what the Xantech interface module does...size of info conversion.
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