We made some changes in audio tests and one of the android bots(android_arm64) is throwing the following exception 

I    0.005s Main  command: /b/build/slave/android_arm64/build/src/webrtc/build/android/test_runner.py gtest --suite common_audio_unittests --shard-timeout 900 --isolate-file-path /b/build/slave/android_arm64/build/src/webrtc/common_audio/common_audio_unittests.isolate --output-directory /b/build/slave/android_arm64/build/src/out/Release --blacklist-file /b/build/slave/android_arm64/build/src/out/bad_devices.json --verbose --adb-path /b/build/slave/android_arm64/build/src/third_party/android_tools/sdk/platform-tools/adb
I    0.006s TimeoutThread-1-for-MainThread  [host]> /b/build/slave/android_arm64/build/src/third_party/android_tools/sdk/platform-tools/adb devices
E    0.014s Main  Error occurred.
Traceback (most recent call last):
  File "/b/build/slave/android_arm64/build/src/build/android/test_runner.py", line 995, in main
    return RunTestsCommand(args)
  File "/b/build/slave/android_arm64/build/src/build/android/test_runner.py", line 818, in RunTestsCommand
    return RunTestsInPlatformMode(args)
  File "/b/build/slave/android_arm64/build/src/build/android/test_runner.py", line 860, in RunTestsInPlatformMode
    with environment_factory.CreateEnvironment(args, infra_error) as env:
  File "/b/build/slave/android_arm64/build/src/build/android/pylib/base/environment.py", line 29, in __enter__
    self.SetUp()
  File "/b/build/slave/android_arm64/build/src/build/android/pylib/local/device/local_device_environment.py", line 68, in SetUp
    raise device_errors.NoDevicesError
NoDevicesError: No devices attached.

Could you please check the issue?