I was having the exact same FRUSTRATING issue. I was dimming rope lights, plugged into a lamp module, and when I hit the dim button on my X-10 Palm Pad, the light would dim all the way down and then everything would freeze until I unplugged the XCVR for a few seconds and plugged back it back in.

I have since added an IR543 and have had NO issues. It seems when the command is initiated through the XCVR it has trouble communicating with the modules and gets "stuck". I'm no expert and maybe someone else can explain better, but the IR543 or other "plug-in" transmitters seem to send a stronger signal to the xcvr.