Lost default ringtones

[stacyt]

Hi, I have the HTC Rezound, and suddenly I've lost all of the default ringtones and default notification sounds (except "facebook pop") Does anyone know what I can do to reload or find the defaults?  (As in, I've checked Settings/Sound/Phone Ringtone and there is nothing to choose from.  I can "add" a ringtone, and it sends me to a list of all of the songs I loaded on the phone)

Thanks for any advice

[demmo86rt]

Have you tried rebooting your phone?

[stacyt]

If you mean power it off, wait and then turn it on again, yes, I tried that.  I have not tried a factory reset as I think that is risky, and if for some reason the files are gone, it may cause more of a problem. Thanks