Here is what I currently have going:
MS14A motion sensor set to A6 (dusk/dawn turned off.....opened motion sensor and put electrical tape over the light sensor as well)
socket rocket and light switch set to A6
I have the MS14A set to send the off command after 3 minutes of no activity. It works great this way for the most part, but sometimes at any given random time it will turn on my A7 light in the basement and it just stays on...so I will come home and have had this big light on all day. Drives me nuts!
Before I fix things... I really like to know what's broken.
For some reason your getting:
(A) An unexpected and random A7 on command on your powerline.
(B) An A7 sent from your MS14A. Which would mean ether the dusk/dawn isn't turn off, the tape has come loose, or the unit is defective.
I'd first look at the macros you already have created and your CM15A's activity log. I've had a similar experience myself.. and found that an incorrect or additional powerline address (like A7) had been placed in a macro. If that A7 is being used, the problem may be from it's macro use... and NOT related to the modified motion sensor.
OR... your MS14A might be malfunctioning. Could the random light not actually be so random as trigger by the light going out on A6. Causing the sensor to see the darkness/dusk. I know you wrote it's turn off and taped. But you could check it with a bright flashlight.
There is also a chance of a misinterpreted command. A command (any command) that the socket rocket set to A7 misinterprets as an A7 ON. Even though it could be anything else. You can check this by setting any other socketrocket to A7.