The problem you describe may be indicative can be caused by a number of things. Bad IR code learns, etc. I presume since you mention 2-way feedback, the receiver is controlled by RS-232. So, now what type of receiver? Did the integrator use one-way RS232 actions, or IR to control the volume?

Why are you asking on his behalf? Is he not familiar with this site? Did the integrator provide you the configuration file used for your remote? Note that you may also require a "My Database" file along with your XCF file if we need to look at what was done.