holley terminator x weird idle change ?????

idle mysteriously changes. fuel pressure is steady at 50 psi. fuel pump, tank and injectors are all new. Kink of hard to hear but it jumps every 4 seconds. Timing is rock steady as well as VE table at idle area. Suggestions?

[@loosescrewdrew]

See what your IAC motor is doing. Sounds like it’s messed up