diff --git a/lib_com/options.h b/lib_com/options.h
index 3c30e33d86a712ab0ef4f87270d26ea19d411eb8..b8567b1503d4c49b523179f7b7e07fd1ab505eac 100644
--- a/lib_com/options.h
+++ b/lib_com/options.h
@@ -149,7 +149,7 @@
 #define FIX_I106_TDREND_5MS                             /* Issue 106: 5 ms update rate in TD object renderer */
 #define ALIGN_SID_SIZE                                  /* Issue 111: make all DTX modes use one SID frame bitrate (5.2 kbps) */
 #define FIX_135_MDCT_STEREO_MODE_UNINITIALIZED          /* Issue 135: fix uninitialized value usage in SBA MDCT-Stereo core with PLC */
-
+#define FIX_CONTROLLABLE_SID_UPDATE_RATE                /* Issue 117: fix controllable SID update rate mechanism */
 
 
 
diff --git a/lib_enc/fd_cng_enc.c b/lib_enc/fd_cng_enc.c
index 670a202df221bf594b739c9f07bbfbeeb048f82d..2f98addc8dca516034c1e26b348cb7ecc4af6ef2 100644
--- a/lib_enc/fd_cng_enc.c
+++ b/lib_enc/fd_cng_enc.c
@@ -902,6 +902,12 @@ void stereoFdCngCoherence(
             sts[0]->core_brate = SID_2k40;
             sts[1]->core_brate = SID_2k40;
         }
+
+#ifdef FIX_CONTROLLABLE_SID_UPDATE_RATE
+        /* synchronize SID counters */
+        sts[0]->hDtxEnc->cnt_SID = min( sts[0]->hDtxEnc->cnt_SID, sts[1]->hDtxEnc->cnt_SID );
+        sts[1]->hDtxEnc->cnt_SID = sts[0]->hDtxEnc->cnt_SID;
+#endif
     }
 
     pt_fftL = fft_buff[0];
@@ -1002,11 +1008,7 @@ void FdCngEncodeMDCTStereoSID(
         convertToMS( N, ms_ptr[0], ms_ptr[1], 0.5f );
     }
 
-    side_energy = 0.0f;
-    for ( p = 0; p < N; p++ )
-    {
-        side_energy += ms_ptr[1][p] * ms_ptr[1][p];
-    }
+    side_energy = sum2_f( ms_ptr[1], N );
 
     /* do not transmit side shape if initial noise shapes are very similar */
     if ( side_energy <= 0.1f )
@@ -1186,18 +1188,11 @@ void FdCngEncodeDiracMDCTStereoSID(
     /* M/S transform on log envelopes */
     convertToMS( NPART, ms_ptr[0], ms_ptr[1], 0.5f );
 
-    E[0] = 0.0f;
-    for ( p = 0; p < NPART; p++ )
-    {
-        E[0] += ms_ptr[0][p];
-    }
+    E[0] = sum_f( ms_ptr[0], NPART );
+
     /* Quantize M noise shape */
     /* Normalize MSVW input */
-    gain[0] = 0.f;
-    for ( p = N_GAIN_MIN; p < N_GAIN_MAX; p++ )
-    {
-        gain[0] += ms_ptr[0][p];
-    }
+    gain[0] = sum_f( ms_ptr[0] + N_GAIN_MIN, N_GAIN_MAX - N_GAIN_MIN );
     gain[0] /= (float) ( N_GAIN_MAX - N_GAIN_MIN );
 
     for ( p = 0; p < N[0]; p++ )
@@ -1213,11 +1208,7 @@ void FdCngEncodeDiracMDCTStereoSID(
     set_zero( ms_ptr[1], NPART );
 
     /* compute M gain */
-    gain[0] = 0.f;
-    for ( p = 0; p < NPART; p++ )
-    {
-        gain[0] += ms_ptr[0][p];
-    }
+    gain[0] = sum_f( ms_ptr[0], NPART );
     gain[0] = ( E[0] - gain[0] ) / (float) N[0];
     apply_scale( &gain[0], sts[0]->hFdCngEnc->hFdCngCom->CngBandwidth, sts[0]->hDtxEnc->last_active_brate, scaleTableStereo, SIZE_SCALE_TABLE_STEREO );