I have been having the same issue and i just got a great solution. My switches WS4777 with soft start were dimming to 100 and then back down. very unappealing and there was a 4 sec or so delay.
I'm very excited because it works so much better now... thanks to boilers post
http://forums.x10.com/index.php?topic=16648.msg91755#msg91755 all you have to do is in active home change the module type to LM14A. Now it issues Extended codes to the WS4777 switches. this is allot more efficient than having to issue an on command and then a dim to 70%. now my lights go straight to 30 % with just issuing an absolute command (with extended codes.)
This was causing all kinds of trouble for me. let me know if this helps and you can work it in to your macros.
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I just noticed you tried defining it as LM14A in activity monitor is it issuing extended codes? what is showing up in activity monitor? Also what versing of AHP do you have installed.
also are you using a repeater? because i know there are known issues with repeaters and the extended codes.
i have an LM465 laying around ill try messing with it later and see if it has the same issues. as my ws4777 switches