AdfitSDK 3.0.7버전으로 업데이트시 Android OS 5.x 이하버전에서 exception 현상 발생

Android 개발자 입니다.

앱에 Adfit 연동하여 사용하고 있습니다.
기존에 adfit 버전 3.0.5을 사용하고 있었으나, 3.0.7버전으로 업데이트시
Android OS 6.0 이상에서는 문제가 없으나
Android OS 5.x 버전 이하 단말에서는 BannerAdView 관련 exception이 발생합니다.

3.0.7버전으로 업데이트시 Android 롤리팝 버전 이하의 단말에서는 추가적으로 별도의 작업이 필요한건지,
아님 Adfit의 버그인건지 해결방법 문의드립니다.

관련 layout 소스 첨부 및 에러내용 첨부합니다.

------- layout xml ---------

            <com.kakao.adfit.ads.ba.BannerAdView
                android:id="@+id/adview"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:visibility="gone"
                />

FATAL EXCEPTION: main
Process:
java.lang.RuntimeException: Unable to start activity ComponentInfo{XXXActivity}: android.view.InflateException: Binary XML file line #76: Error inflating class com.kakao.adfit.ads.ba.BannerAdView
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2305)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363)
at android.app.ActivityThread.access$900(ActivityThread.java:161)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
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:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Caused by: android.view.InflateException: Binary XML file line #76: Error inflating class com.kakao.adfit.ads.ba.BannerAdView
at android.view.LayoutInflater.createView(LayoutInflater.java:626)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:702)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:761)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.inflate(LayoutInflater.java:498)
at android.view.LayoutInflater.inflate(LayoutInflater.java:398)
at android.view.LayoutInflater.inflate(LayoutInflater.java:354)
at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:359)
at android.app.Activity.setContentView(Activity.java:2010)
at packagename.XXXActivity.onCreate(XXXActivity.java:240)
at android.app.Activity.performCreate(Activity.java:5426)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2269)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363)
at android.app.ActivityThread.access$900(ActivityThread.java:161)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
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:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Constructor.constructNative(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at android.view.LayoutInflater.createView(LayoutInflater.java:600)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:702)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:761)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.inflate(LayoutInflater.java:498)
at android.view.LayoutInflater.inflate(LayoutInflater.java:398)
at android.view.LayoutInflater.inflate(LayoutInflater.java:354)
at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:359)
at android.app.Activity.setContentView(Activity.java:2010)
at packagename.XXXActivity.onCreate(XXXActivity.java:240)
at android.app.Activity.performCreate(Activity.java:5426)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2269)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363)
at android.app.ActivityThread.access$900(ActivityThread.java:161)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
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:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.kakao.adfit.ads.ba.BannerAdView.onVisibilityChanged(BannerAdView.kt:265)
at android.view.View.dispatchVisibilityChanged(View.java:8404)
at android.view.ViewGroup.dispatchVisibilityChanged(ViewGroup.java:1070)
at android.view.View.setFlags(View.java:9732)
at android.view.View.(View.java:4081)
at android.view.ViewGroup.(ViewGroup.java:480)
at android.widget.RelativeLayout.(RelativeLayout.java:242)
at com.kakao.adfit.ads.ba.BannerAdView.(BannerAdView.kt:26)
at com.kakao.adfit.ads.ba.BannerAdView.(BannerAdView.kt:25)
at com.kakao.adfit.ads.ba.BannerAdView.(BannerAdView.kt)
at java.lang.reflect.Constructor.constructNative(Native Method)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at android.view.LayoutInflater.createView(LayoutInflater.java:600)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:702)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:761)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:769)
at android.view.LayoutInflater.inflate(LayoutInflater.java:498)
at android.view.LayoutInflater.inflate(LayoutInflater.java:398)
at android.view.LayoutInflater.inflate(LayoutInflater.java:354)
at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:359)
at android.app.Activity.setContentView(Activity.java:2010)
at packagename.XXXActivity.onCreate(XXXActivity.java:240)
at android.app.Activity.performCreate(Activity.java:5426)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2269)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2363)
at android.app.ActivityThread.access$900(ActivityThread.java:161)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1265)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5356)
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:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)