iOS device video with ID Core 10 used as audio source

[ccjmusic]

Has anybody successfully used an iPhone or iPad to record a video with the audio coming directly from the amp via USB? I have tried connecting using the Camera Kit for connecting the amp to both my iPhone and iPad and none of the video apps I have tried will work. Even apps like Filmic Pro where I can set the sample rate to 48 Khz. The majority of the time the record functionality is disabled and a recording can't be started, or it starts and records nothing, shutting off again after a second or so. In one case (Musemage) it shows a dialog saying the video is corrupted and cannot be saved. Devices are iPhone SE and iPad Mini, both are 64GB and the iOS version on both devices is 12.2. The amp has the latest firmware installed via Insider. Any ideas or suggestions on how to record directly?

TIA

Colin

PS. I can record the audio to Garageband but it gets the glitch every few seconds from not being a 48 Khz app.