Map_background problem =P Thread

Hey guys,
Hoping someone could help me out here - not sure what this is and its starting to piss me off

Yeah sorry this is the first time I have mapped for a menu background =/
But I have never come across this before, If anyone could point out what could be the cause of this bastard please tell me
The entities i currently have on the map are:

• light_environment
• env_flame
• prop_static (quite a few)
• prop_dynamic
• env_embers
• path_corner (many for the combine to walk around)
• npc_combine_s + npc_rollermine
• player spawn
• point_viewcontrol
• logic_auto

Judging by the color im assuming its the light but if anyone could help me out it would be great. Thanks

you know what... It was the env_embers colliding with the smoke

well hope that helps anyone who encounters this unusual problem =/

Cheers guys