title: Xcode Audio Unit v3 template fails validation
body: <p>I've created a little test app with an Audio Unit extension via the following steps:</p>
  
  <ol>
  <li>Open Xcode and create a new "Cocoa Application" project</li>
  <li>Select File -> New -> Target</li>
  <li>Select "Audio Unit extension"</li>
  <li>Fill out the form with reasonable values (I've tested both Instrument and Midi Effect types)</li>
  <li>"Run" the Extension</li>
  <li>Select "Logic Pro X" as the host app</li>
  <li>Logic starts and plugin validation fails: <code>While verifying Audio Unit compatibility, Logic Pro X encountered 1 Audio Unit plug-in(s) which did not pass the Apple AU validation. These plug-ins have been excluded from further usage in Logic Pro X to prevent possible problems or crashes. You can start the Plug-In Manager now to review the validation results or continue the startup process.</code></li>
  </ol>
  
  <p>Just to be clear, <strong>I did not edit the template code at all.</strong></p>
  
  <p>When I run <code>auval</code> I get the following:</p>
  
  <pre>
  validating Audio Unit Instrument by ADLS:
  
      AU Validation Tool
      Version: 1.6.1a1 
      Copyright 2003-2013, Apple Inc. All Rights Reserved.
      Specify -h (-help) for command options
  
  --------------------------------------------------
  VALIDATING AUDIO UNIT: 'aumu' - 'qqqq' - 'ADLS'
  --------------------------------------------------
  Manufacturer String: ADLS
  AudioUnit Name: Instrument
  Component Version: 1.6.0 (0x10600)
  
  * * PASS
  --------------------------------------------------
  TESTING OPEN TIMES:
  COLD:
  Time to open AudioUnit:         213.911 ms
  WARM:
  Time to open AudioUnit:         100.937  ms
  This AudioUnit is a version 3 implementation.
  FIRST TIME:
  FATAL ERROR: Initialize: result: -50
  
  
  validation result: couldn't be opened
  </pre>
  
  <p>I would assume Apple's templates are correct, so this may be a configuration problem on my system. Indeed, I get the following disconcerting message in the Xcode console:</p>
  
  <pre>
  2016-08-31 13:15:25.602 Logic Pro X[51763:12817003] 13:15:25.602 WARNING:
    140: This application, or a library it uses, is using the deprecated Carbon
   Component Manager for hosting Audio Units. Support for this will be 
  removed in a future release. Also, this makes the host incompatible with 
  version 3 audio units. Please transition to the API's in AudioComponent.h.
  </pre>
  
  <p>Most likely there is some other Audio Unit that is using the <code>Component Manager</code>, since I'm creating a brand new app using Xcode's template.</p>
  
  <p>However, Apple's own AUV3FilterDemo works correctly. So perhaps this message is a red herring.</p>
  
  <p>Are Apple's templates supposed to validate out of the box?</p>
  
  <p><strong>Update</strong></p>
  
  <p>By removing other plugins I was able to avoid the v2 API warning, so it was indeed a red herring.</p>