Timers create Lua errors

[Butthurt]

function CLASS:OnSpawn( ply )
	
	local enttab = ents.GetAllAliveTiles()
	
	if( #enttab > 0 ) then
		
		local ent = table.Random( enttab )
		ply:SetPos( ent.Pos + Vector( 0, 0, 32 ) )
		
			timer.Simple( 3, function()
				
				ent:EmitSound( table.Random( ent.ActivateSounds ), 66, math.random( 70, 130 ) )
				ent:SetColor( 255, 0, 0, 255 )
				ent.Dropped = true
				
			end )
			
			timer.Simple( 3, function()
				
				ent:EmitSound( table.Random( ent.FallSounds ), 33, math.random( 70, 130 ) )
				ent:Drop()
				
			end )
		
	end
	
	ply:SetGravity( 1 )
	
end

This works but create lua error.

[ERROR] lua/includes/extensions/table.lua:161: bad argument #1 to 'pairs' (table expected, got nil)
  1. pairs - [C]:-1
   2. Count - lua/includes/extensions/table.lua:161
    3. Random - lua/includes/extensions/table.lua:173
     4. unknown - gamemodes/******/gamemode/player_class/class_default.lua:36

Timer Failed! [Simple][@gamemodes/*****/gamemode/player_class/class_default.lua (line 34)]


[ERROR] lua/includes/extensions/table.lua:161: bad argument #1 to 'pairs' (table expected, got nil)
  1. pairs - [C]:-1
   2. Count - lua/includes/extensions/table.lua:161
    3. Random - lua/includes/extensions/table.lua:173
     4. unknown - gamemodes/******/gamemode/player_class/class_default.lua:44

Timer Failed! [Simple][@gamemodes/*******/gamemode/player_class/class_default.lua (line 42)]

[Ott]

ent.ActivateSounds and/or ent.FallSounds are nil.

[UnkN]

Try test if value is table, if type(enttab) == table then
Try check in timer entity valid, timer( if IsValid(ent) then code end)
local ent = table.Random(enttab)
ent = enttab[ent]
Try talso that.

[Butthurt]

[QUOTE=Ott;45659922]ent.ActivateSounds and/or ent.FallSounds are nil.[/QUOTE]

function CLASS:OnSpawn( ply )
	
	local enttab = ents.GetAllAliveTiles()
	local ent = table.Random( enttab )
	
	if( #enttab > 0 ) then
		
		ply:SetPos( ent.Pos + Vector( 0, 0, 82 ) )
		
			timer.Simple( 3, function()
				
				ent:SetColor( 255, 0, 0, 255 )
				ent:EmitSound( "physics/metal/sawblade_stick1.wav", 66, math.random( 70, 130 ) )
				ent.Dropped = true
				
			end )
			
			timer.Simple( 4, function()
				
				ent:EmitSound( "doors/vent_open3.wav", 33, math.random( 70, 130 ) )
				ent:Drop()
				
			end)
	end
	
	ply:SetGravity( 1 )
	
end

but now other error

[ERROR] gamemodes/*****/gamemode/player_class/class_default.lua:36: Tried to use a NULL entity!
  1. SetColor - [C]:-1
   2. unknown - gamemodes/*****/gamemode/player_class/class_default.lua:36

Timer Failed! [Simple][@gamemodes/******/gamemode/player_class/class_default.lua (line 34)]

[ERROR] gamemodes/*****/gamemode/player_class/class_default.lua:44: Tried to use a NULL entity!
  1. EmitSound - [C]:-1
   2. unknown - gamemodes/*****/gamemode/player_class/class_default.lua:44

Timer Failed! [Simple][@gamemodes/******/gamemode/player_class/class_default.lua (line 42)]

* ents.GetAllAliveTiles()

function ents.GetAllAliveTiles()
	
	local tab = { }
	
	for _, v in pairs( ents.FindByClass( "til_tile" ) ) do
		
		if( !v.Dropped ) then
			
			table.insert( tab, v )
			
		end
		
	end
	
	return tab
	
end