I have a 1 inch plastic conduit and am running about 100 feet underground?
You best safe guard is to use UTP for the wiring - that way you will be sure there will be no hassles
Joists are not wall studs. They bear weight and load differently. Drill a 1/2 to 3/4 inch hole through the joist at least 2inches up from the bottom, or dry wall side. Any lower and you can serious damage and weaken the joist in your ceiling. Good Luck
Quite possibly, yes. Wires with current running through them generate a magnetic field, which can induce a current in another conductor. The induced current would be audible as what's called a 60 cycle hum. If the speaker wire you use is shielded, with a braided metallic outer layer, the induced current can be greatly reduced or even eliminated entirely. The shield should be grounded at the amplifier end.
Running electrical wire and any other wiring in the same conduit is against electrical code. It is potentially dangerous and could cause damage to your equipment, shock hazards to the users, and possibly start a fire. Don't do it. Your insurance company wouldn't cover any damage from this illegal wiring.
