Can't compile app Error code 1

Question

I'm trying to use the aacdecoder library to listen an online radio in my app, the thing is that it doesn't compile, I have added the jar library and added to the build.gradle, this is my code

MultiPlayer aacMp3Player = new MultiPlayer();
aacMp3Player.playAsync( "http://cast.direcnode.com:11413/stream" );

And this is the error:

Error:Execution failed for task ':app:dexDebug'.
> com.android.ide.common.internal.LoggedErrorException: Failed to run command:
/Users/Ger/Documents/sdk/build-tools/android-4.4W/dx --dex --num-threads=4 --output /Users/Ger/Desktop/Radio/app/build/intermediates/dex/debug /Users/Ger/Desktop/Radio/app/build/intermediates/classes/debug /Users/Ger/Desktop/Radio/app/build/intermediates/dependency-cache/debug /Users/Ger/Desktop/Radio/app/build/intermediates/pre-dexed/debug/aacdecoder-android-0.8-470e8c408147266db0ce9215156fc542209cf849.jar
Error Code:
1

This is my build.gradle:

apply plugin: 'com.android.application'

android {
compileSdkVersion 21
buildToolsVersion "20.0.0"

defaultConfig {
    applicationId "ger.radio"
    minSdkVersion 14
    targetSdkVersion 21
    versionCode 1
    versionName "1.0"
}
buildTypes {
    release {
        runProguard false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}
compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_7
    targetCompatibility JavaVersion.VERSION_1_7
}
}

dependencies {
compile files('lib/aacdecoder-android-0.8.jar')
compile fileTree(dir: 'lib', include: ['*.jar'])
}

task copyNativeLibs(type: Copy) {
from(new File('libs')) { include '**' }
into new File(buildDir, 'native-libs')
}