xrecord EXIT code null signal SIGSEGV

Trying to record video on iphone 6s with wpt 3.0. This is the only active iphone attached to the host, but there is an android also attached. Video on the android works, but with the iphone we constantly get the SIGSEGV message and

WebDriverServer. : Exception from “Process Video”: Error: Command Timeout

with a visual progress indicator that reaches 100% but the test hangs after that. We’re not sure if were missing a step or config option