MOVING RIGHT ALONG: I.R.S. Records keeps saying there's no truth to those rumors that R.E.M. might be heading for more--ahem--Virgin pastures. And we're inclined to agree, especially since R.E.M. will release not one but two I.R.S. albums this year. The group is heading for Nashville next month, where they'll start work on a new album with producer Scott Litt. Meanwhile, the band has prepared a treat for hard-core fans, a collection of oddities called "Dead Letter Office," which is due out in May. The compilation, which offers impish liner notes by Peter Buck, includes a host of obscure cover versions, including Aerosmith's "Toys in the Attic," "King of the Road" (complete with a Walter's Bar-B-Q commercial), a trio of Lou Reed tunes (including "Femme Fatale") and a R.E.M. original called "Windout," which originally appeared (of all places) on the "Bachelor Party" sound track. I.R.S. execs say the CD version of the album will also include the group's "Chronic Town" EP, which has never been available on compact disc. To make things even more complicated, "Dead Letter" will be distributed not by MCA but A&M Records, which has retained the rights to most of R.E.M.'s old tracks.