diff --git a/src/random.c b/src/random.c
index 34b8380d..14676057 100644
--- a/src/random.c
+++ b/src/random.c
@@ -33,6 +33,7 @@
 #include "flash.h"
 #ifndef TESTING
 #include "ataes132.h"
+#include "utils.h"
 #include "sha2.h"
 #include "mcu.h"
 
@@ -65,54 +66,67 @@ uint32_t random_uint32(uint8_t update_seed)
 
 int random_bytes(uint8_t *buf, uint32_t len, uint8_t update_seed)
 {
+#ifdef TESTING
+    // Use standard libary for off chip RNG
     uint32_t i = 0;
-#ifndef TESTING
-    const uint8_t ataes_cmd[] = {0x02, 0x02, 0x00, 0x00, 0x00, 0x00}; // Pseudo RNG
-    const uint8_t ataes_cmd_up[] = {0x02, 0x00, 0x00, 0x00, 0x00, 0x00}; // True RNG - writes to EEPROM
-    uint8_t ret, ataes_ret[20] = {0}; // Random command return packet [Count(1) || Return Code (1) | Data(16) || CRC (2)]
-
-    while (len > i) {
-        if (update_seed) {
-            ret = ataes_process(ataes_cmd_up, sizeof(ataes_cmd_up), ataes_ret, sizeof(ataes_ret));
-            update_seed = 0;
-        } else {
-            ret = ataes_process(ataes_cmd, sizeof(ataes_cmd), ataes_ret, sizeof(ataes_ret));
-        }
-        if (ret == DBB_OK && ataes_ret[0]) {
-            memcpy(buf + i, ataes_ret + 2, (len - i) < 16 ? (len - i) : 16);
-        } else {
-            HardFault_Handler();
-            return DBB_ERROR;
-        }
-        i += 16;
+    (void) update_seed;
+    for (i = 0; i < len; i++) {
+        buf[i] = rand();
     }
+#else
+    uint32_t i = 0, n = 0;
 #ifndef BOOTLOADER
-    // Add ataes independent entropy from second chip (MCU UID)
-    uint8_t entropy[32];
+    uint8_t entropy[32], usersig[FLASH_USERSIG_SIZE] = {0};
     uint32_t serial[4] = {0};
+
+    // Add entropy from second chip (MCU UID)
     flash_read_unique_id(serial, 4);
     sha256_Raw((uint8_t *)serial, sizeof(serial), entropy);
-    for (i = 0; i < sizeof(serial); i++) {
+    for (i = 0; i < MAX(len, sizeof(serial)); i++) {
         buf[i % len] ^= entropy[i % MEM_PAGE_LEN];
     }
-    // Add ataes independent entropy from random bytes set during factory install
+    // Add entropy from random bytes set during factory install
     sha256_Raw((uint8_t *)(FLASH_BOOT_START), FLASH_BOOT_LEN, entropy);
     sha256_Raw(entropy, sizeof(entropy), entropy);
     sha256_Raw(entropy, sizeof(entropy), entropy);
-    for (i = 0; i < MEM_PAGE_LEN; i++) {
+    for (i = 0; i < MAX(len, MEM_PAGE_LEN); i++) {
         buf[i % len] ^= entropy[i % MEM_PAGE_LEN];
     }
-    // Add ataes independent entropy from user (hashed device password)
+    // Add entropy from user (hashed device password)
     memcpy(entropy, memory_report_user_entropy(), sizeof(entropy));
-    for (i = 0; i < MEM_PAGE_LEN; i++) {
+    for (i = 0; i < MAX(len, MEM_PAGE_LEN); i++) {
         buf[i % len] ^= entropy[i % MEM_PAGE_LEN];
     }
+    // Add entropy from usersig
+    flash_read_user_signature((uint32_t *)usersig, FLASH_USERSIG_SIZE / sizeof(uint32_t));
+    sha256_Raw(usersig, FLASH_USERSIG_SIZE, entropy);
+    for (i = 0; i < MAX(len, MEM_PAGE_LEN); i++) {
+        buf[i % len] ^= entropy[i % MEM_PAGE_LEN];
+        usersig[i % FLASH_USERSIG_RN_LEN] = entropy[i % MEM_PAGE_LEN];
+    }
 #endif
-#else
-    // Use standard libary for off chip RNG
-    (void) update_seed;
-    for (i = 0; i < len; i++) {
-        buf[i] = rand();
+    // Add entropy from ataes RNG
+    const uint8_t ataes_cmd[] = {0x02, 0x02, 0x00, 0x00, 0x00, 0x00}; // Pseudo RNG
+    const uint8_t ataes_cmd_up[] = {0x02, 0x00, 0x00, 0x00, 0x00, 0x00}; // True RNG - writes to EEPROM
+    uint8_t ret, ataes_ret[20] = {0}; // Random command return packet [Count(1) || Return Code (1) | Data(16) || CRC (2)]
+    while (len > n) {
+        if (update_seed) {
+            ret = ataes_process(ataes_cmd_up, sizeof(ataes_cmd_up), ataes_ret, sizeof(ataes_ret));
+            update_seed = 0;
+        } else {
+            ret = ataes_process(ataes_cmd, sizeof(ataes_cmd), ataes_ret, sizeof(ataes_ret));
+        }
+        if (ret == DBB_OK && ataes_ret[0] && !ataes_ret[1]) {
+            for (i = 0; i < MIN(len - n, 16); i++) {
+                buf[(n + i) % len] ^= ataes_ret[(2 + i) % sizeof(ataes_ret)];
+            }
+        } else {
+            flash_erase_user_signature();
+            flash_write_user_signature((uint32_t *)usersig, FLASH_USERSIG_SIZE / sizeof(uint32_t));
+            HardFault_Handler();
+            return DBB_ERROR;
+        }
+        n += 16;
     }
 #endif
     return DBB_OK;