Getting GCM Error: INVALID_SENDER occasionally

Getting GCM Error: INVALID_SENDER occasionally

I inherited an application that already implemented GCM services as is
working well enough. I'm saying well enough because half the times when
the app launches I get the error INVALID_SENDER and the other half I dont
get it ! There is no difference between the times I get the error and the
times that i dont. (or maybe i'm missing the difference)
This is the registration code in the onCreate() of my main activity
private void registerGCM() throws Exception {
GCMRegistrar.checkDevice(this);
GCMRegistrar.checkManifest(this);
registerReceiver(mHandleMessageReceiver, new IntentFilter(
CommonUtilities.DISPLAY_MESSAGE_ACTION));
final String regId = GCMRegistrar.getRegistrationId(this);
if (regId.equals("")) {
// Automatically registers application on startup.
GCMRegistrar.register(this, CommonUtilities.SENDER_ID);
} else {
// Device is already registered on GCM, check server.
if (GCMRegistrar.isRegisteredOnServer(this)) {
ServerUtilities.register(mContext, regId);
} else {
// Try to register again, but not in the UI thread.
// It's also necessary to cancel the thread onDestroy(),
// hence the use of AsyncTask instead of a raw thread.
final Context context = this;
mRegisterTask = new AsyncTask<Void, Void, Void>() {
@Override
protected Void doInBackground(Void... params) {
boolean registered = ServerUtilities.register(context,
regId);
if (!registered) {
GCMRegistrar.unregister(context);
}
return null;
}
My Manifest file
<receiver
android:name="com.mixpanel.android.mpmetrics.GCMReceiver"
android:permission="com.google.android.c2dm.permission.SEND" >
<intent-filter>
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
<action
android:name="com.google.android.c2dm.intent.REGISTRATION" />
<category android:name="com.says.broadcaster" />
</intent-filter>
</receiver>
<receiver
android:name="com.google.android.gcm.GCMBroadcastReceiver"
android:permission="com.google.android.c2dm.permission.SEND" >
<intent-filter>
<!-- Receives the actual messages. -->
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
<!-- Receives the registration id. -->
<action
android:name="com.google.android.c2dm.intent.REGISTRATION" />
<category android:name="com.says.broadcaster" />
</intent-filter>
</receiver>
The reason I have two receivers is that I get push notifications from the
stats tracking API i'm using too. And they use GCM.
My app has a new version every week or so, and I was reading that i need
to register for a new ID after an app update. Could this be the issue?
Related questions: Getting INVALID_SENDER on one device while its working
with another GCM android