Filed under: Portable AudioIf you woke up this morning worried about what Yahoo! is planning to do for its Music Store customers who are about to be left in the lurch with its DRM server shut-down, have no fear. Yahoo! has announced that it will offer customers coupons or refunds for those songs you bought. Basically, you'll get a coupon that you can use at RealNetworks Inc.'s Rhapsody download service. Their songs, of course, are DRM-free. For those of you who have "serious problems with this arrangement" (their words, not ours), refunds will be available. The servers go down on September 30, so start comb