From CloudModding OoT Wiki
Actor 0x003B
ovl_En_River_Sound
Version VRom VRam Size
Debug 00E9C910 00E9D290 {{{ram-start}}} {{{ram-end}}} 980
NTSC 1.0 00C69630 00C69FC0 {{{ram-start}}} {{{ram-end}}} 990
PAL MQ 00E38010 00E389A0 {{{ram-start}}} {{{ram-end}}} 990

ovl_En_River_Sound is an actor used to play various sound effects.