android studio)level26端末のみ落ちる

以前に作成したAndroidアプリのAPIレベルを25から26に上げました。gradleで変更してsyncするとAPIの数か所警告エラーになったので
メッセージ通りレベルを変更修正してsyncもクリアしました。
しかしエミュレータで試してみると25までの端末は問題なくコンパイルできるのですが
26の端末で試すと落ちてしまいます。どんな理由が考えられるか分かる方教えて下さい。
開発環境）
Android Studio　3.1.4
pc : mac

gradle(module app)

apply plugin: 'com.android.application'

android {
    compileSdkVersion 26
    buildToolsVersion '27.0.3'
    defaultConfig {
        applicationId "com.○○○○.wordapp"
        minSdkVersion 21
        targetSdkVersion 26
        versionCode 19
        versionName "2.5.2"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        debug {
            minifyEnabled true
            useProguard false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'

        }
        release {
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}
dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    androidTestImplementation('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    implementation 'com.github.bumptech.glide:glide:3.7.0'
    implementation 'com.android.support:support-v4:26.1.0'
    implementation 'com.google.firebase:firebase-ads:15.0.1'
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.1.2'
    implementation 'com.android.support:recyclerview-v7:26.1.0'
    implementation 'com.android.support:cardview-v7:26.1.0'
    testImplementation 'junit:junit:4.12'
}
apply plugin: 'com.google.gms.google-services'

gradle(project)

buildscript {
    repositories {
        jcenter()
        google()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.1.4'
        classpath 'com.google.gms:google-services:4.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}
allprojects {
    repositories {
        jcenter()
        maven{
            url "https://maven.google.com"
        }
        google()
    }
}
task clean(type: Delete) {
    delete rootProject.buildDir
}

error Log

08-25 15:53:14.320 2054-5745/com.android.systemui E/ResourcesManager: failed to add asset path /data/app/com.○○○○.wordapp-HP3_KdeG951jwS_H5rYAoA==/base.apk
08-25 15:53:14.342 2054-5745/com.android.systemui E/ResourcesManager: failed to add asset path /data/app/com.○○○○.wordapp-HP3_KdeG951jwS_H5rYAoA==/base.apk
08-25 15:53:14.353 2054-5745/com.android.systemui E/ResourcesManager: failed to add asset path /data/app/com.○○○○.wordapp-HP3_KdeG951jwS_H5rYAoA==/base.apk
08-25 15:53:14.410 2054-5745/com.android.systemui E/ResourcesManager: failed to add asset path /data/app/com.○○○○.wordapp-HP3_KdeG951jwS_H5rYAoA==/base.apk
08-25 15:53:14.769 2054-5745/com.android.systemui E/ResourcesManager: failed to add asset path /data/app/com.○○○○.wordapp-HP3_KdeG951jwS_H5rYAoA==/base.apk
08-25 15:53:14.769 2054-5745/com.android.systemui E/ResourcesManager: failed to add asset path /data/app/com.○○○○.wordapp-HP3_KdeG951jwS_H5rYAoA==/base.apk
08-25 15:53:14.889 1422-1662/? E/IPCThreadState: binder thread pool (4 threads) starved for 211 ms
08-25 15:53:15.464 1559-2307/? E/AudioFlinger: not enough memory for AudioTrack size=131296
08-25 15:53:15.464 1559-2307/? E/AudioFlinger: createRecordTrack_l() initCheck failed -12; no control block?
08-25 15:53:15.465 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord: AudioFlinger could not create record track, status: -12
08-25 15:53:15.470 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -12.
08-25 15:53:15.471 2931-7113/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
08-25 15:53:15.571 2931-7113/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
08-25 15:53:16.087 1728-2033/system_process E/TaskPersister: File error accessing recents directory (directory doesn't exist?).
08-25 15:53:20.623 1559-2307/? E/AudioFlinger: not enough memory for AudioTrack size=131296
08-25 15:53:20.623 1559-2307/? E/AudioFlinger: createRecordTrack_l() initCheck failed -12; no control block?
08-25 15:53:20.623 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord: AudioFlinger could not create record track, status: -12
08-25 15:53:20.630 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -12.
08-25 15:53:20.630 2931-7113/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
08-25 15:53:20.638 2931-7113/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
08-25 15:53:25.663 1559-2307/? E/AudioFlinger: not enough memory for AudioTrack size=131296
08-25 15:53:25.663 1559-2307/? E/AudioFlinger: createRecordTrack_l() initCheck failed -12; no control block?
08-25 15:53:25.663 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord: AudioFlinger could not create record track, status: -12
08-25 15:53:25.665 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -12.
08-25 15:53:25.665 2931-7113/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
08-25 15:53:25.667 2931-7113/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
08-25 15:53:28.711 1728-2033/system_process E/TaskPersister: File error accessing recents directory (directory doesn't exist?).
08-25 15:53:30.702 1559-2307/? E/AudioFlinger: not enough memory for AudioTrack size=131296
08-25 15:53:30.702 1559-2307/? E/AudioFlinger: createRecordTrack_l() initCheck failed -12; no control block?
08-25 15:53:30.702 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord: AudioFlinger could not create record track, status: -12
08-25 15:53:30.705 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -12.
08-25 15:53:30.705 2931-7113/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.
08-25 15:53:30.705 2931-7113/com.google.android.googlequicksearchbox:search E/ActivityThread: Failed to find provider info for com.google.android.apps.gsa.testing.ui.audio.recorded
08-25 15:53:35.755 1559-2307/? E/AudioFlinger: not enough memory for AudioTrack size=131296
08-25 15:53:35.756 1559-2307/? E/AudioFlinger: createRecordTrack_l() initCheck failed -12; no control block?
08-25 15:53:35.756 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord: AudioFlinger could not create record track, status: -12
08-25 15:53:35.759 2931-7113/com.google.android.googlequicksearchbox:search E/AudioRecord-JNI: Error creating AudioRecord instance: initialization check failed with status -12.
08-25 15:53:35.762 2931-7113/com.google.android.googlequicksearchbox:search E/android.media.AudioRecord: Error code -20 when initializing native AudioRecord object.