diff --git a/widgets/alsabar.lua b/widgets/alsabar.lua
index 9fe5339..15ba311 100644
--- a/widgets/alsabar.lua
+++ b/widgets/alsabar.lua
@@ -19,6 +19,7 @@ local string       = { format = string.format,
                        match  = string.match,
                        rep    = string.rep }
 local tonumber     = tonumber
+local type         = type
 
 local setmetatable = setmetatable
 
@@ -101,7 +102,7 @@ local function worker(args)
 
                 settings()
 
-                if callback then callback() end
+                if type(callback) == "function" then callback() end
             end
         end)
     end
diff --git a/widgets/fs.lua b/widgets/fs.lua
index d5dd49a..f07ef98 100644
--- a/widgets/fs.lua
+++ b/widgets/fs.lua
@@ -98,7 +98,7 @@ local function worker(args)
             widget = fs.widget
             settings()
 
-            if notify == "on" and fs_now.used >= 99 and not helpers.get_map(partition) then
+            if notify == "on" and tonumber(fs_now.used) >= 99 and not helpers.get_map(partition) then
                 naughty.notify({
                     title   = "warning",
                     text    = partition .. " is empty!",