Just two years ago, rap-metal yowled its way to the top. Groups such as Korn, Limp Bizkit, Rage Against the Machine, Papa Roach, Linkin Park and Crazytown dominated rock.

In the last year, that trend has shown signs of lightening up. In some cases, artists’ sales have flattened or plummeted. In others, bands decided to change their sound, perhaps jumping before being pushed.

Crazytown, a hip-hop/hard rock act, sold 1.6 million copies of its 1999 debut album, “The Gift of Game,” at the trend’s peak in 2000. But the band’s follow up has been a disaster.

In mid-November, “Darkhorse,” opened at an awful No. 120 on Billboard’s Top 200, with sales of 12,843 copies. Five weeks later, it has vanished from the Top 200 with total sales of only 35,000.

Crazytown can’t blame radio for its crash. Its song “Drowning” made the top 20 of both modern-rock and mainstream-rock radio formats. Listeners simply were unimpressed with what they heard.

Korn, likewise, continues to enjoy major rock radio play. And its sales aren’t exactly poor, at 1.2 million copies of its fifth and latest work, “Untouchables.” Still, that’s only one-third of what its previous two albums sold. Worse, nearly half the new CD’s sales came in its first week, suggesting poor word of mouth.

Perhaps anticipating such a droop, Papa Roach — whose major-label debut, 2000’s “Infested,” rode the rock-rap wave with 3.2 million copies sold — has rejiggered its sound somewhat. Its second album “LoveHateTragedy” inched toward mainstream rock and punk, but apparently not far or fast enough to save Roach from being squashed. Its latest album has managed only 550,000 sales.

Rock-rap mainstay Rage Against the Machine has disbanded (due to personal squabbles). It has been replaced by the hip-hop-free Audioslave (a supergroup combo of Rage’s three musicians with singer Chris Cornell from defunct band Soundgarden). Yet, its self-titled debut album hasn’t sold in supergroup numbers. After four weeks, it’s at a tepid No. 51.

Meanwhile, another group of rock-rap louts, Limp Bizkit, is among the missing, ever since it lost guitarist Wes Borland. But Linkin Park, which had the largest-selling album of 2001, plans to release its second work in March, hopefully to comparable sales.