少数用户的Android dalvik错误（Android版本4.4）

一些应用程序用户收到此错误消息，应用程序崩溃。此错误日志来自Google控制台。所有这些错误都发生在Android版本4.4上。有没有关于如何解决这个问题的建议

这是gradle设置。我的应用程序不是很复杂。它有Admob库

apply plugin: 'com.android.application'

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.2"

    defaultConfig {
        applicationId "com.mycompany.app1"
        minSdkVersion 14
        targetSdkVersion 25
        multiDexEnabled true
        setProperty("archivesBaseName", "APP")
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.txt'
        }
    }

    dexOptions {
        javaMaxHeapSize "4g"
    } }

dependencies {
    compile 'com.google.android.gms:play-services:+'

编译'com.android.support:multidex:1.0.1'}

Today, 4:49 AM on app version 34
Samsung Galaxy Grand2 (ms013g), 1536MB RAM, Android 4.4
Report 32 of 2,511

    java.lang.RuntimeException: 
      at android.app.ActivityThread.installProvider (ActivityThread.java:5256)
      at android.app.ActivityThread.installContentProviders (ActivityThread.java:4847)
      at android.app.ActivityThread.handleBindApplication (ActivityThread.java:4730)
      at android.app.ActivityThread.access$1600 (ActivityThread.java:172)
      at android.app.ActivityThread$H.handleMessage (ActivityThread.java:1368)
      at android.os.Handler.dispatchMessage (Handler.java:102)
      at android.os.Looper.loop (Looper.java:146)
      at android.app.ActivityThread.main (ActivityThread.java:5653)
      at java.lang.reflect.Method.invokeNative (Native Method)
      at java.lang.reflect.Method.invoke (Method.java:515)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1291)
      at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1107)
      at dalvik.system.NativeStart.main (Native Method)
    Caused by: java.lang.ClassNotFoundException: 
      at dalvik.system.BaseDexClassLoader.findClass (BaseDexClassLoader.java:67)
      at java.lang.ClassLoader.loadClass (ClassLoader.java:497)
      at java.lang.ClassLoader.loadClass (ClassLoader.java:457)
      at android.app.ActivityThread.installProvider (ActivityThread.java:5241)