Wiring suround sound speakers
Well, the amount of current going through surround sound speaker wire is not sufficient enough to start a fire, so that is a minimal concern.
However, I would probably go for a nice finish personally. Find some spring clip or binding post wall sockets and install them to the drywall using coarse screws.
Fishing the wire through the wall can be a challenge, especially if there is insulation or firebreaks in there. You might want to use an electronic studfinder to make sure there are no firebreaks in the way before you start drilling. Fishing it out is probably easiest with 2 people, drill the hole in the wall and then one directly above it in the attic through the top of the 2x4 on the wall. Make it big enough to put a small washer on a string and then have someone down below pull it out of the wall with a magnet or a magnetized screwdriver. Then you will be able to tie the string to the wire and pull it up - and on the second side, pull the wire down.