Issue 3306. Better control for a lenght in findmax() function.
diff --git a/Modules/audioop.c b/Modules/audioop.c
index 31e3fa4..767cae6 100644
--- a/Modules/audioop.c
+++ b/Modules/audioop.c
@@ -575,7 +575,7 @@
         }
         len1 >>= 1;
     
-        if ( len1 < len2 ) {
+        if ( len2 < 0 || len1 < len2 ) {
                 PyErr_SetString(AudioopError, "Input sample should be longer");
                 return 0;
         }