Well, you're right--the speaker is 8 ohms according to my multimeter, but the earphone I'm using is showing a range of 2-5M Ohms. It's one of those old crystal radio earphones that looks like this. My regular headphones, though, are showing 32 ohms.
Anyway, I wouldn't be surprised if I've already fried the chip, so when I get the new one, I'll connect the audio out to the RCA plug as shown in the schematic I previously linked to.