Invisible/Inaudable Zombies since 1.5.7?

[grofit 0]

I have put a bug report down in the bug forum which I think needs moderating, but while I am waiting for that is no one else having problems seeing zombies since the latest patch?

On Monday night I was playing on 1.5.6 killing zombies, then had to update to 1.5.7 and I thought nothing of it, as my friends were screaming that zombies were incoming but as I cannot see anything at night time anyway I thought nothing of it. Then last night I was playing and had a chemlight on and so did another guy near me, anyway again my friends said there were zombies outside the house, but I could not see them, and then they said they were coming right at us. I couldn't see or hear them and suddenly im in the middle of a gunfight with my blood going down with no visible enemy.

I checked the floor for corpses as they were saying I was standing on one, and couldnt see it, so given that I cannot see the 10x as many zombies as there were I am unable to play for the moment.

Is anyone else suffering from this? I have re-applied the patch files and I dont get any errors when loading/joining so I am a bit baffled.