REAPER loses the audio device when your interface drops on a Mac
REAPER is about as robust as DAWs get, which makes this one especially irritating: the interface drops for a second, and REAPER goes quiet. Sometimes you get a clear message that the audio device is unavailable. Sometimes the transport rolls on with no meters moving. Either way you're into Options → Device settings to reset the device while the clock is running.
The cause isn't REAPER, and the fix isn't a preference. Here's the mechanism and the durable answer.
Why it happens
On macOS, REAPER opens your interface through Core Audio and binds to that specific device — its identity, its channel count, its sample rate. Your track inputs and hardware outputs are all expressed in terms of that device's channels.
A USB drop removes the device from Core Audio entirely. The device REAPER opened is simply gone, so the audio engine has nothing to pull from and stops.
When the interface re-appears, macOS re-enumerates it and re-registers it. It may come back with a different internal identity or a different stream layout. REAPER may reopen it, may reopen it with channels in a different order, or may need an explicit device reset — and any track inputs pinned to specific channel numbers can end up pointing somewhere you didn't intend. That last one is the dangerous failure, because it isn't silent: it records, just from the wrong source.
What helps, and how far
Reset the device. Options → Device settings, then close and reopen the audio device. The standard recovery. Fast once you've done it a few times, but it's still a recovery.
Check "close audio device when stopped" is off for live work. Letting the device close and reopen gives you extra chances to hit exactly this problem at exactly the wrong moment.
Pin your sample rate and block size explicitly rather than following the device, so a reconnect at a different rate doesn't silently change your session's timing assumptions.
Sort out the physical layer. Direct port, powered interface, decent cable, current firmware, sleep disabled. Always worth it; makes drops rare rather than routine.
Verify inputs after any drop. Especially with high channel counts, confirm that track 12 is still listening to input 12.
None of this stops the device from being removed. It just gets you back faster and reduces how often you need to.
The durable fix
Open a stable device that mirrors your interface in REAPER, instead of opening the interface directly.
The mirror doesn't leave Core Audio, so REAPER's audio device is never removed. The engine keeps running, the channel map stays exactly as you set it, and there is no device to reset. The interface drops and returns behind the mirror; audio stops and resumes; your session's I/O never moves.
Keel Audio provides that on macOS — a transparent, bit-for-bit mirror of one interface, on the interface's own clock, with no processing applied. Point REAPER at the Keel device once and the USB layer stops being your problem. One-time purchase, full 14-day trial; the honest test is to unplug the interface while the transport is rolling and watch the channel map hold.
One clarification, because it comes up: this isn't a router, a virtual cable, or a mixer for moving sound between apps. It does a single job — keep one physical interface rock-stable for whatever depends on it.
Checklist
- Direct USB port; avoid hubs and shared docks.
- Powered interface, secured cable, current firmware.
- Open a stable device in REAPER rather than the raw interface.
- Turn off "close audio device when stopped" for live work.
- Pin sample rate and block size explicitly.
- Dry-run a disconnect before anything depends on the rig.
Bottom line
REAPER stops because its device was deleted, not because it gave up. Make drops rare by fixing the physical layer, then make them harmless by giving REAPER a device that can't be deleted — and the worst a kicked cable can do is interrupt the sound, not rearrange your session.
Keel Audio keeps one audio interface rock-stable on macOS, so a USB drop never resets your DAW or kills your stream.
Try it free for 14 days →