attempt to perform arithmetic on local 'num' (a nil value)

Been getting this error, and it comes and goes with no real consistency. Some times it doesnt appear when joining, sometimes it does. Restarting the server generally causes it to not show up the next time I join but it appears to be at random. Not sure whats causing it.

[ERROR] lua/includes/extensions/math.lua:156: attempt to perform arithmetic on local 'num' (a nil value)
  1. Round - lua/includes/extensions/math.lua:156
   2. DrawHUD - addons/ahud/lua/ahud/ahud.lua:203
    3. v - addons/ahud/lua/ahud/ahud.lua:419
     4. unknown - lua/includes/modules/hook.lua:84

This is line 156:

return math.floor( num * mult + 0.5 ) / mult

This is part of the math.Round function.
An addon is running math.Round without a number.
That addon appears to be this:


Check line 203 of that file.