diff --git a/src/libiir/400_parser.c b/src/libiir/400_parser.c
index 107f51e..604aed6 100644
--- a/src/libiir/400_parser.c
+++ b/src/libiir/400_parser.c
@@ -103,8 +103,13 @@ iir_parser_raw(struct iir_filter_t** fi, const char* desc)
  *  The maximum order in any single Butterworth-type filter. If the given order
  *  exceeds this, we split the resulting filter up into multiple sets of
  *  coefficients of this order or less.
+ *
+ *  This is required since IIR filters, even with double-precision floating
+ *  point numbers, are particularly susceptible to quantization errors. In
+ *  practice, anything with a steeper roll-off than 2nd order can go unstable
+ *  when presented with real input data.
  */
-#define IIR_PARSER_BW_MAX_ORDER         (4)
+#define IIR_PARSER_BW_MAX_ORDER         (2)
 
 
 
@@ -176,7 +181,7 @@ iir_parser_bw_aux2(struct iir_filter_t** fi,
         }
         iir_coeff_free(coeff);
         if(!order) return 0;
-        /* add a <4th order segment */
+        /* add a <2nd order segment */
     }
 
     coeff = bw(order, gain, corner);
@@ -214,7 +219,7 @@ iir_parser_bw_aux3(struct iir_filter_t** fi,
         }
         iir_coeff_free(coeff);
         if(!order) return 0;
-        /* add a <4th order segment */
+        /* add a <2nd order segment */
     }
 
     coeff = bw(order, gain, c1, c2);