distributed home audio stumper... can anyone help?

i work for a custom home audio and theatre business. i was recently called out to a job at a newly constructed office for a contractor. i was called out to troubleshoot a distributed audio system that they couldnt quite get to work. they had the problem of frying their stereo receivers two of them to be exact. so the first thing i asked was who wired everything. their response was their electrician did. i dont know about anyone else, but when a home audio guy hears those words we cringe. so after looking all around the building they have 5 volume controls that were not impedence matching, an impedence matching distribution hub, and a main lead from the receivers location to the distribution panel. so first i checked the impedence at the receiver end of the system and it reads 1 ohm!!! well thats why they were frying receivers. so i go back to the distribution and meter there and it says 4 OHMs. so after looking for quite some time i found what seemed to be a short in a pair of the wires. fixed that then it at least is reading 4 OHMs at the receiver. still not quite to the stable 8 OHMs that 95% of home equipment operates at. so all the leads coming into the distribution read 4 OHMs. so i go back to my store, grab five nxg 80watt impedence matching volume controls and head back to the job. i pull the previous controls out and meter the speakers. they read 6 OHM. now keep in mind this is a brand new building and "the electrician knew what he was doing". so if anyone is familliar with the nxg volume controls they have a ticker to switch the amount of speakers are coming off the lead. so i set the ticker to 2x because that is the smallest setting on the control. so i hook everything up, go to meter the lead from the receiver to check for 8 OHMs and i have a whopping 4 ohms. i unhook two volume controls and it goes to 7 OHMS i then set the tickers on the controls to 4x which should increase the impedence just to see what my reading would be at the amp. after hooking all the controls back up and switching the impedence on the controls to 16X which is way more than it should be i was able to get the reading to 9 OHMs. Does anyone know what the hell the electrician could have done to create such a mess. it needs to be fixed and im stumped. oh and the electrician no longer works with the company... i wonder why. If you have any suggestions im up for any suggestions at all.