Problem with iCloud downloads

When the iTunes iCloud beta first started, everything was working great on my iPhone, iPad and iMac, but the last few days my iPhone has been deleting my entire iPod library whenever I try to download a song from iCloud.

After purchasing a song from either the iPad or iMac (both of which are not experiencing this problem), the iPhone does in fact auto download the songs, as it is supposed to do, but the songs never actually appear in my iPod app. If I then manually redownload the purchased songs, my entire library will be gone when I return to the iPod app. In the "About" section of Settings, the iPhone says there are no songs on the phone, but no additional space has freed up on the device.

If I sync my phone to my iMac after this happens, no music will appear to resync to the phone, but my library will be totally restored after syncing is completed.

Pretty wierd huh? Any ideas?