I'll answer here, although an Atlas hardly falls into the "Pro remote" category.
Probably the Power key has a macro assigned to it that is overriding the behavior you want.
Use the 9XX command instructions
to clear the possible macro. Use the 995 command, paying attention to step 4, which tells how to clear an existing macro.
Is this a 1056B01 or B03? If it is a B01, tell us the the brand and model of your cable box, and we can probably suggest an alternate fix using keymoves (994).
If it is a B03, or previous efforts don't fix the problem, I recommend trying next the 977 command, which may restore the remote to the configuration installed by the cable company. Next you can do a 980 reset, but that may erase a cable-company installed upgrade. Finally, you can do a 981 reset, which will put the remote into the base configuration. 981 will definitely remove any functionality installed by the cable company.