diff --git a/Cabal/Distribution/Compat/Time.hs b/Cabal/Distribution/Compat/Time.hs
index 2a6a8ea0c41..a3f4895ed6d 100644
--- a/Cabal/Distribution/Compat/Time.hs
+++ b/Cabal/Distribution/Compat/Time.hs
@@ -16,8 +16,8 @@ import Distribution.Compat.Prelude
 
 import System.Directory ( getModificationTime )
 
-import Distribution.Simple.Utils ( withTempDirectory )
-import Distribution.Verbosity ( silent )
+import Distribution.Simple.Utils ( debug, withTempDirectory )
+import Distribution.Verbosity ( deafening, silent )
 
 import System.FilePath
 
@@ -193,10 +193,11 @@ calibrateMtimeChangeDelay =
     sampleMtimes :: FilePath -> IO [Int]
     sampleMtimes fileName = do
       mtime0 <- sampleMtime 1 fileName
+      debug deafening $ "mtime0: " ++ show mtime0
       -- Some filesystems (e.g. HFS+ on Mac) store mtimes with 1
       -- second resolution. Bail out directly instead of spinning in
       -- that case.
-      if (mtime0 >= 1000000) || (1000000 - mtime0 <= 10000)
+      if (mtime0 >= 1000000) || (1000000 - mtime0 <= 100000)
         then return [mtime0]
         else do mtimes <- for [2..25] $ \(i::Int) -> sampleMtime i fileName
                 return (mtime0:mtimes)