Sandoval had never used two bass drums before joining Morbid Angel. He had to practice frequently in order to get his feet up to speed, and recorded the Altars of Madness album within only a couple of months of joining Morbid Angel. According to Morbid Angel guitarist Trey Azagthoth, the band would occasionally walk in on Sandoval passed out on the floor in a pool of sweat. After being woken up, he would immediately say, "Time to get back to work!" After mastering double-bass usage in Morbid Angel, Sandoval also implemented them in Terrorizer's World Downfall album when the band briefly re-united to record it.
According to singer David Vincent, the band once played a prank on Sandoval by making him listen to a band that used a preprogrammed drum machine, and pretended it was a real drummer who could play faster than he could. Sandoval was gutted, and went on to practice until he managed to play faster than the machine.
In 2010, he had to undergo surgery to repair a prolapsed disc. Not being able to play painlessly for an extended period for up to a year, he was replaced by Tim Yeung for the recording and touring of Morbid Angel's 2011 album Illud Divinum Insanus.
In December of 2013, David Vincent stated in an interview that Sandoval was no longer with Morbid Angel, citing incompatibility with the band after Sandoval's conversion to Christianity as the reason.