Frequently Asked Questions

My LTC timecode cable or headphone-jack adapter worked fine with MovieSlate on my older device, but since updating to a current version of iOS it no longer feeds timecode into the app. What changed?

Apple significantly tightened the requirements for external audio inputs in recent iOS/iPadOS releases (iOS 18 and iOS 26). To be accepted as an external audio input, cables and adapters must now conform to Apple's Made for iPhone (MFi) program. Older, non-MFi cables and adapters that worked for years — including ones used with MovieSlate 7 — will often no longer pass audio into the app on an up-to-date device.
This is an iOS-level change, not a MovieSlate bug. There is no setting in MovieSlate that can work around it.

How to tell this is what's happening

1. In MovieSlate, go to Settings > Timecode + Sync > Test Headphone Connection.
2. With your timecode source running, watch the level meter. If it shows nothing, the input isn't reaching the app.
3. Clap your hands near the device. If the meter reacts to the clap, iOS is still listening to the built-in microphone — meaning your cable or adapter is not being accepted as an external input.

What to do

• Replace the adapter with an MFi-compliant one. The Apple USB-C to 3.5mm Headphone Jack Adapter is the most reliable choice.
• Make sure the timecode cable itself has a TRRS connector (four contacts) on the end that goes into the device — a TRS cable will never work for audio input on iOS, MFi or not.
• Check the current list of cables and adapters PureBlend has tested at movie-slate.com/Timecode_Cables/.
• Confirm MovieSlate has microphone access under Settings > Privacy & Security > Microphone.