diff --git a/EIPS/eip-1057.md b/EIPS/eip-1057.md
index 82807941..e85d218e 100644
--- a/EIPS/eip-1057.md
+++ b/EIPS/eip-1057.md
@@ -251,8 +251,9 @@ void merge(uint32_t &a, uint32_t b, uint32_t r)
     {
     case 0: a = (a * 33) + b; break;
     case 1: a = (a ^ b) * 33; break;
-    case 2: a = ROTL32(a, ((r >> 16) % 32)) ^ b; break;
-    case 3: a = ROTR32(a, ((r >> 16) % 32)) ^ b; break;
+    // prevent rotate by 0 which is a NOP
+    case 2: a = ROTL32(a, ((r >> 16) % 31) + 1) ^ b; break;
+    case 3: a = ROTR32(a, ((r >> 16) % 31) + 1) ^ b; break;
     }
 }
 ```
@@ -329,8 +330,11 @@ void progPowLoop(
         if (i < PROGPOW_CNT_MATH)
         {
             // Random Math
-            int src1 = kiss99(prog_rnd) % PROGPOW_REGS;
-            int src2 = kiss99(prog_rnd) % PROGPOW_REGS;
+            // Generate 2 unique sources 
+            int src_rnd = kiss99(prog_rnd) % (PROGPOW_REGS * (PROGPOW_REGS-1));
+            int src1 = src_rnd % PROGPOW_REGS; // 0 <= src1 < PROGPOW_REGS
+            int src2 = src_rnd / PROGPOW_REGS; // 0 <= src2 < PROGPOW_REGS - 1
+            if (src2 >= src1) ++src2; // src2 is now any reg other than src
             int sel1 = kiss99(prog_rnd);
             int dst  = mix_seq_dst[(mix_seq_dst_cnt++)%PROGPOW_REGS];
             int sel2 = kiss99(prog_rnd);