Audio Systems: stereo pops, weird sound, left speaker

Question
My 1989 saab's front left speaker pops intermittently.  Sometimes it happens many times in a row, and I have to turn it off.  Then when I turn it back on it will sometimes make a weird sound.  Then it can go for months on end with no problem at all.  It is normally worst when it is wet outside.  Is my problem in the speaker or the head unit?  I have been told both, and I don't know who to believe.  Thank you.

Answer
Charles,

 well they are both right it can be in either one but if only one speaker is affected then more than likly its just that speaker .. pull your head unit out and give a good inspection of the wires to make sure everything is insulated and looks good and tight .. then turn on your unit and wiggle the harness and note the changes in the sound if there is any dramatic changes you might be looking at a new re-wire of the sound system ... but thats not to common but more common in older model cars ... ok my recommendation is to buy a new set of front speakers nothing fancy unless you are planning on a high end system build up .. you can pick up a set for around 20 dollars see if that doesnt cure the problem .. hope this helps you out if you need anything else let me know

thanks