Trying to think this through as an EASA 21J HOA and CVE. The behaviour you describe doesn't sound acceptable to this low time PPL, so is the system correctly implemented, set-up and maintained? (Lesson learnt long ago as a junior development engineer, when someone tells you the design is wrong, first check that they made it to the design). There must be a STC for the modification kit (well, assuming that the aircraft is not registered Experimental and that its type certificate and CofA are still valid) so the first thing is to check that you have a legal modification and that it is correctly implemented. A quick search on the FAA website suggests that FAA STCs can be found via the link below. Look under By STC Holder for "
Sierra Industries, Inc, Garner Field Road Uvalde TX 78801 United States". There is a long list, you'll have to find the one or more that apply, it should be recorded in the aircraft paperwork.
http://rgl.faa.gov/Regulatory_and_Gu...e?OpenFrameSet
That should get you started.