imimot Mitti troubleshooting

Common Mitti errors & problems

What techs run into most, and what's usually behind it. The step-by-step fix for your exact software is in Ask Roadie.

• Audio and video are out of sync on a Blackmagic (SDI) output

  Likely cause: Routing audio through the BMD native driver clocks it to the same reference as the video output, whereas the Core Audio route runs on a separate clock and drifts.

  Step-by-step fixGet the fix →

• Blackmagic capture device not recognized or shows no input

  Likely cause: BMD hardware needs its driver to enumerate; many cards cannot auto-detect the incoming standard so a format mismatch yields black; and HDCP encryption blocks capture by design.

  Step-by-step fixGet the fix →

• Fullscreen output does not appear on the external screen / display shows as disconnected

  Likely cause: Mitti binds outputs to specific display configs; when the physical display or its resolution differs from the saved project, the output stays mapped to the missing screen until you point it at the live one.

  Step-by-step fixGet the fix →

• Keyer / alpha option is greyed out on a Blackmagic card that supports keying

  Likely cause: The alpha/keyer path in Mitti is implemented only for the 8-bit render pipeline, so enabling 10-bit removes the alpha channel the keyer needs.

  Step-by-step fixGet the fix →

• Large playlist triggers slowly or plays choppy; how much RAM does Mitti need

  Likely cause: Because each cue is preloaded, total playlist size scales with memory; running past the RAM budget forces paging and produces slow triggering and dropped frames.

  Step-by-step fixGet the fix →

• Mitti stuck on "Connecting..." spinning wheel when connecting to an ATEM switcher

  Likely cause: The ATEM protocol version is carried by the driver; a stale driver cannot complete the handshake, and a mismatched subnet mask puts the two devices on different logical networks.

  Step-by-step fixGet the fix →

• Mitti will not launch or hangs at startup

  Likely cause: Mitti reads its saved defaults at launch; a malformed value throws during init, so clearing/rebuilding the preference or taking the 2.8.17 fix lets it start.

  Step-by-step fixGet the fix →

• NMC computers do not see each other at all

  Likely cause: NMC uses Bonjour/mDNS for discovery; app firewalls and the macOS 15 Local Network privacy gate silently block those multicast packets until Mitti is explicitly allowed.

  Step-by-step fixGet the fix →

• NMC net-sync instances see each other but will not communicate / sync

  Likely cause: NMC relies on routable private-range UDP; link-local/APIPA addresses and mismatched subnet masks block the packet path, and wireless loses the UDP transport it depends on.

  Step-by-step fixGet the fix →

• OSC / OSCQuery control stops working after upgrading to macOS 15 Sequoia

  Likely cause: macOS 15 added a Local Network privacy gate that blocks the UDP/mDNS traffic OSC, OSCQuery, NDI discovery and ATEM detection rely on until the app is explicitly allowed.

  Step-by-step fixGet the fix →

• Playback stutters, freezes, or files will not load from a network/NAS drive

  Likely cause: Mitti preloads and streams frames in real time; network latency and throughput cannot guarantee the sustained read rate GPU-accelerated playback needs, causing stalls.

  Step-by-step fixGet the fix →

• Preview inside Mitti UI stutters but the actual program output is smooth

  Likely cause: The separate-Spaces setting changes how macOS composites windows across displays, resolving the UI-preview render contention that does not affect the dedicated output pipeline.

  Step-by-step fixGet the fix →

Not on the list? Describe it your way, or paste the error code off the display. Ask Roadie works the problem with you until it's fixed or you have a clear next move.

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