spawn rate in some mondains dungeons

I've noticed that the spawn rate in some of the mondain's legacy dungeons is much lower than on p2p shard which makes it very difficult to collect peerless keys. I spent a total of nearly 4 hours today in the prism of light collecting keys. It wouldn't be so bad if it was 4 hours of fighting, but waiting around for mobs to spawn is boring. on top of that, your other keys start to poof while you are waiting for mobs to spawn. I had a similar experience in bedlam trying to get the keys there. the mobs spawn so slowly that by the time you get a few keys they start to disapear waiting for mobs. Is there any way to increase the spawn rate for the key monsters?

I will be happy to look into it.
As for the set rate times that is how ml has them set up not us so it helps to know what is spawning slower then others in those area's. Thanks