The reason I asked was, the delays incorporated in PBP for X10 commands assume a 60 Hz system; if you are in a 50 Hz country, you might have to tweak some values in the XIN and XOUT routines in the .lib files, especially if your transmitter and receiver are not on the same phase.

When I design around X10 (my hardware directly interfaces with the mains), I do use the XOUT, but for receiving I decode the incoming signal manually.

What I'd suggest is, record the zerp crossing signals on one channel and the X10 signals on the other channel using your sound card, and see what you're actually getting. Confirm if the X10 bits are withing the tolerated delay of a true zero crossing. Decode the bit stream to see if it matches the transmitted signal. That would be a starting point.

Regards,

Anand