Device Not Detected: Troubleshooting

Quick Assessment

Answer these questions to identify your issue type:

1

How are you connecting?

2

What device are you using?

3

What exactly happens?

Universal Checklist

Try these steps in order. Most issues are resolved by steps 1-3.

Try a different USB cable Most common fix

~80% of detection issues are cable-related. Test with 2-3 different cables.

Unplug everything and reconnect

Disconnect all cables, wait 5 seconds, then reconnect in this order: power (if applicable) first, then USB.

Power cycle the keyboard

Turn the keyboard completely off, wait 10 seconds, then turn it back on.

Check keyboard USB port selection

Use the "USB to Host" or "MIDI Out" port on your keyboard. Don't use "USB to Device" (that's for flash drives).

Force-close and restart Crescendo

Swipe up from the bottom of the screen and swipe the app away. Then reopen.

Restart your phone/tablet

A full device restart clears any stuck MIDI processes.

Still not working? Continue to the platform-specific sections below.

Platform-Specific Troubleshooting

iOS USB Issues

Most iOS detection issues are adapter-related

Third-party adapters often don't work with MIDI devices due to MFi certification requirements. Use Apple's official adapters for best results.

Using Apple's official Lightning/USB-C adapter? Critical

Lightning devices: Use "Lightning to USB 3 Camera Adapter" (~$35) for power passthrough.
USB-C devices: Use a direct USB-C to USB-B cable or Apple's USB-C adapter.

Seeing "This accessory uses too much power"?

Your keyboard needs more power than the device can provide. Solutions:
1. Use Lightning to USB 3 Camera Adapter + plug in a charger
2. Use a powered USB hub
3. Power the keyboard separately (if it has a power jack)

Seeing "This accessory is not supported"?

Usually means adapter isn't MFi certified. Try:
1. Use a genuine Apple adapter
2. Update to the latest iOS version
3. Clean the Lightning/USB-C port

Check iOS version

Crescendo requires iOS 12+. For best USB MIDI stability, use iOS 15.5+.
Go to Settings → General → Software Update.

iOS Bluetooth Issues

Pair within Crescendo, not iOS Settings

Bluetooth MIDI uses a different protocol than regular Bluetooth audio. You must pair using the "Scan for Bluetooth MIDI" button inside Crescendo.

Keyboard in Bluetooth pairing mode?

Check your keyboard manual. Most keyboards have a dedicated Bluetooth button or Function + Bluetooth key combination.

Within 10 feet (3 meters)?

Bluetooth MIDI has limited range. Move closer during initial pairing.

Toggle Bluetooth off and on

Go to Settings → Bluetooth, toggle off, wait 5 seconds, toggle on. Then try scanning again in Crescendo.

See detailed iOS USB guide → | See detailed iOS Bluetooth guide →

Android USB Issues

Most Android detection issues are OTG-related

Android doesn't assume USB host mode by default. You need an OTG adapter and may need to enable OTG in settings.

Using an OTG adapter (not charging-only)? Critical

The adapter must explicitly say "OTG" in the product name. Charging-only adapters look identical but won't work for MIDI.

OTG enabled in phone settings? Critical for some phones

Google Pixel, Samsung: Auto-enabled
OnePlus: Settings → Additional Settings → OTG
Xiaomi/MIUI: Settings → Additional Settings → OTG Connection
Oppo/Realme: Settings → Additional Settings → OTG Connection

OTG auto-disabled after 10 minutes? OnePlus, Xiaomi, Oppo

Some phones disable OTG automatically to save battery. If your keyboard suddenly stops being detected mid-session, re-enable OTG in settings.

Developer Options: USB Configuration set to MIDI?

On some devices (especially Xiaomi):
1. Enable Developer Options (tap Build Number 7 times)
2. Go to Settings → Developer Options → USB Configuration
3. Select "MIDI"

Check Android version

Crescendo requires Android 6.0+ (MIDI API introduced in API 23).
Go to Settings → About Phone → Android Version.

Android Bluetooth Issues

Pair within Crescendo, not Android Settings

Bluetooth MIDI uses BLE MIDI protocol. You must pair using the "Scan for Bluetooth MIDI" button inside Crescendo.

Android limitation: May need to reconnect each session

Unlike iOS, Android's BLE MIDI doesn't reliably auto-reconnect. Previously paired devices may appear "connected" but need a fresh scan to actually work.

Bluetooth permissions granted? Android 12+

Android 12+ requires "Nearby devices" permission. When Crescendo asks, tap "Allow".

"Ghost device" issue?

If your keyboard appears in the list but won't connect, it may be a "ghost" entry. Tap "Scan for Bluetooth MIDI" again to discover the actual device.

Toggle Bluetooth off and on

Go to Settings → Bluetooth, toggle off, wait 5 seconds, toggle on. This clears the Bluetooth cache.

Samsung device? Known issue

Samsung phones have known BLE reconnection issues. If Bluetooth stops working, toggle Bluetooth off/on in system settings.

See detailed Android USB guide → | See detailed Android Bluetooth guide →

Power Issues (Bus-Powered Keyboards)

What is a bus-powered keyboard?

A bus-powered keyboard draws all its electrical power from the USB connection (no separate power adapter). These keyboards may exceed the USB power limit of your phone/tablet.

Symptoms of Power Issues

Keyboard detected but immediately disconnects
"This accessory uses too much power" (iOS)
Keyboard works briefly then stops
Keys light up but no MIDI signal

Solutions

1

Use an adapter with power passthrough (iOS)

Apple's "Lightning to USB 3 Camera Adapter" has a Lightning port for charging while the keyboard is connected. Plug in your charger to provide extra power.

2

Use a powered USB hub

A powered USB hub (with its own power adapter) provides unlimited power to connected devices. Connect the hub to your phone/tablet, then connect the keyboard to the hub.

3

Power the keyboard separately

If your keyboard has a DC power input (9V or 12V jack), use the keyboard's power adapter. This takes the power load off the USB connection.

Adapter Quality Issues

iOS Adapter Requirements

Recommended

Apple Lightning to USB 3 Camera Adapter (~$35)
Apple USB-C Digital AV Multiport Adapter (~$69)
Direct USB-C to USB-B cable (for USB-C devices)

Avoid

Non-MFi certified adapters
Generic "Lightning to USB" adapters
Adapters without power passthrough (for bus-powered keyboards)

Android Adapter Requirements

Recommended

USB-C to USB-A OTG adapter with "OTG" label
Brands: Anker, UGREEN, Cable Matters
Powered USB-C hub (for power-hungry keyboards)

Avoid

Charging-only adapters (look identical but no OTG)
Generic no-brand adapters
Daisy-chained adapters/hubs

How to test if your adapter supports OTG (Android)

Connect a USB flash drive using the adapter. If your phone can read files from the drive, the adapter supports OTG. If nothing happens, the adapter is charging-only.

iOS Update Compatibility

iOS updates occasionally cause MIDI detection issues. Here are known issues and workarounds:

iOS 15.4 - MIDI devices stopped working

Issue: Some Yamaha and other MIDI keyboards stopped being detected after updating to iOS 15.4.

Workaround: Use traditional MIDI DIN cables with an iRig-style adapter instead of USB.

Resolution: Fixed in iOS 15.5. Update to iOS 15.5 or later.

iOS 18 - CoreMIDI crashes

Issue: "MIDIServer exceeded mem limit" errors causing MIDI apps to freeze or crash.

Workaround: Restart your iPad/iPhone to clear the issue. Avoid running multiple MIDI-enabled apps simultaneously.

Status: Reported to Apple. Watch for fixes in future iOS updates.

General: Accessory not supported after iOS update

Issue: "This accessory is not supported" appears for adapters/keyboards that previously worked.

Possible causes:

iOS update changed MFi certification requirements
Third-party adapter no longer passes compatibility checks

Solution: Use Apple's official adapters, which are always updated for compatibility.

Best practice before updating iOS

Before major iOS updates, check online forums and communities to see if other users report MIDI issues with the new version.

When to Get More Help

If you've tried everything above and your keyboard still isn't detected:

Interactive MIDI Troubleshooter

Step-by-step decision tree for all MIDI issues

Connection Guide

Complete setup instructions from scratch

Contact Support

If you've completed this entire checklist and still have issues, please contact us. Include the following information:

Device model (e.g., iPhone 14 Pro, Samsung Galaxy S23)
OS version (e.g., iOS 17.2, Android 14)
Keyboard model and brand
Connection type (USB or Bluetooth)
Adapter type (if applicable)
What you tried from this checklist
Exact error message (if any)

Email Support