diff --git a/Classes/LinphoneAppDelegate.m b/Classes/LinphoneAppDelegate.m
index fdbdc782a..51cb4a8ff 100644
--- a/Classes/LinphoneAppDelegate.m
+++ b/Classes/LinphoneAppDelegate.m
@@ -57,7 +57,7 @@
     NSMutableDictionary *defaultsToRegister = [[NSMutableDictionary alloc] initWithCapacity:[preferences count]];
     for(NSDictionary *prefSpecification in preferences) {
         NSString *key = [prefSpecification objectForKey:@"Key"];
-        if(key) {
+        if(key && [prefSpecification objectForKey:@"DefaultValue"]) {
             [defaultsToRegister setObject:[prefSpecification objectForKey:@"DefaultValue"] forKey:key];
         }
     }
diff --git a/Classes/LinphoneUI/LinphoneManager.m b/Classes/LinphoneUI/LinphoneManager.m
index f97158161..b87078e3c 100644
--- a/Classes/LinphoneUI/LinphoneManager.m
+++ b/Classes/LinphoneUI/LinphoneManager.m
@@ -242,7 +242,7 @@ static LinphoneCoreVTable linphonec_vtable = {
 -(void) configurePayloadType:(const char*) type fromPrefKey: (NSString*)key withRate:(int)rate  {
 	if ([[NSUserDefaults standardUserDefaults] boolForKey:key]) { 		
 		PayloadType* pt;
-		if(pt = linphone_core_find_payload_type(theLinphoneCore,type,rate)) {
+		if((pt = linphone_core_find_payload_type(theLinphoneCore,type,rate))) {
 			linphone_core_enable_payload_type(theLinphoneCore,pt, TRUE);
 		}
 	}