diff --git a/bubble-server/src/main/java/bubble/service/cloud/StandardDeviceIdService.java b/bubble-server/src/main/java/bubble/service/cloud/StandardDeviceIdService.java
index 153540c6..7cee2577 100644
--- a/bubble-server/src/main/java/bubble/service/cloud/StandardDeviceIdService.java
+++ b/bubble-server/src/main/java/bubble/service/cloud/StandardDeviceIdService.java
@@ -56,6 +56,10 @@ public class StandardDeviceIdService implements DeviceIdService {
     // used in dnscrypt-proxy to determine how to respond to blocked requests
     public static final String REDIS_KEY_DEVICE_REJECT_WITH = "bubble_device_reject_with_";
 
+    // used in mitmproxy to optimize passthru requests
+    // we flush keys with this prefix when changing showBlockStats flag
+    public static final String REDIS_KEY_CHUNK_FILTER_PASS = "__chunk_filter_pass__";
+
     @Autowired private DeviceDAO deviceDAO;
     @Autowired private AccountDAO accountDAO;
     @Autowired private RedisService redis;
@@ -154,6 +158,7 @@ public class StandardDeviceIdService implements DeviceIdService {
 
     public void initBlockStats (Account account) {
         redis.set_plaintext(REDIS_KEY_ACCOUNT_SHOW_BLOCK_STATS+account.getUuid(), Boolean.toString(account.showBlockStats()));
+        redis.del_withPrefix(REDIS_KEY_CHUNK_FILTER_PASS);
         for (Device device : deviceDAO.findByAccount(account.getUuid())) {
             if (account.showBlockStats()) {
                 showBlockStats(device);