diff --git a/src/EngineMkI.cpp b/src/EngineMkI.cpp
index 6f8f200..d6b3f6b 100644
--- a/src/EngineMkI.cpp
+++ b/src/EngineMkI.cpp
@@ -338,6 +338,10 @@ void EngineMkI::render(int32_t *output, FmOpParams *params, int algorithm, int32
                             params[1].phase += params[1].freq << LG_N;  // yuk, hack, we already processed op-5
                             op++; // ignore next operator;
                             break;
+                        case 31 :
+                            // one operator feedback, process exception for ALGO 32
+                            compute_fb(outptr, param.phase, param.freq, gain1, gain2, fb_buf, min((feedback_shift+2), 16), add);
+                            break;
                         default:
                             // one operator feedback, normal proces
                             compute_fb(outptr, param.phase, param.freq, gain1, gain2, fb_buf, feedback_shift, add);