diff --git a/src/bbl_rx.c b/src/bbl_rx.c
index da573dfb..a74affb1 100644
--- a/src/bbl_rx.c
+++ b/src/bbl_rx.c
@@ -457,7 +457,7 @@ bbl_igmp_zapping(timer_s *timer)
     struct timespec time_diff;
     struct timespec time_now;
 
-    int ms;
+    uint32_t ms;
 
     if(session->session_state != BBL_ESTABLISHED ||
        session->ipcp_state != BBL_PPP_OPENED) {
@@ -483,9 +483,10 @@ bbl_igmp_zapping(timer_s *timer)
     group = session->zapping_joined_group;
     if(group->first_mc_rx_time.tv_sec) {
         timespec_sub(&time_diff, &group->first_mc_rx_time, &group->join_tx_time);
-        ms = round(time_diff.tv_nsec / 1.0e6); // Convert nanoseconds to milliseconds
+        ms = time_diff.tv_nsec / 1000000; // convert nanoseconds to milliseconds
+        if(time_diff.tv_nsec % 1000000) ms++; // simple roundup function
         join_delay = (time_diff.tv_sec * 1000) + ms;
-
+        if(!join_delay) join_delay = 1; // join delay must be at least one millisecond
         session->zapping_join_delay_sum += join_delay;
         session->zapping_join_delay_count++;
         if(join_delay > session->stats.max_join_delay) session->stats.max_join_delay = join_delay;
@@ -530,8 +531,10 @@ bbl_igmp_zapping(timer_s *timer)
     group = session->zapping_leaved_group;
     if(group->group && group->last_mc_rx_time.tv_sec && group->leave_tx_time.tv_sec) {
         timespec_sub(&time_diff, &group->last_mc_rx_time, &group->leave_tx_time);
-        ms = round(time_diff.tv_nsec / 1.0e6); // Convert nanoseconds to milliseconds
+        ms = time_diff.tv_nsec / 1000000; // convert nanoseconds to milliseconds
+        if(time_diff.tv_nsec % 1000000) ms++; // simple roundup function
         leave_delay = (time_diff.tv_sec * 1000) + ms;
+        if(!leave_delay) leave_delay = 1; // leave delay must be at least one millisecond
         session->zapping_leave_delay_sum += leave_delay;
         session->zapping_leave_delay_count++;
         if(leave_delay > session->stats.max_leave_delay) session->stats.max_leave_delay = leave_delay;
diff --git a/src/bbl_stats.c b/src/bbl_stats.c
index a08b1ffe..b9c38a36 100644
--- a/src/bbl_stats.c
+++ b/src/bbl_stats.c
@@ -55,8 +55,8 @@ bbl_stats_generate (bbl_ctx_s *ctx, bbl_stats_t * stats) {
     bbl_session_s *session;
     uint32_t i;
 
-    int join_delays = 0;
-    int leave_delays = 0;
+    uint32_t join_delays = 0;
+    uint32_t leave_delays = 0;
 
     bbl_stats_update_cps(ctx);
 
@@ -142,10 +142,10 @@ bbl_stats_generate (bbl_ctx_s *ctx, bbl_stats_t * stats) {
         }
     }
     if(join_delays) {
-        stats->avg_join_delay = round(stats->avg_join_delay / join_delays);
+        stats->avg_join_delay = stats->avg_join_delay / join_delays;
     }
     if(leave_delays) {
-        stats->avg_leave_delay = round(stats->avg_leave_delay / leave_delays);
+        stats->avg_leave_delay = stats->avg_leave_delay / leave_delays;
     }
 }
 
diff --git a/src/bbl_tx.c b/src/bbl_tx.c
index 72f77a5c..37469c35 100644
--- a/src/bbl_tx.c
+++ b/src/bbl_tx.c
@@ -295,7 +295,6 @@ bbl_encode_packet_igmp (bbl_session_s *session)
             if(group->robustness_count) {
                 group->robustness_count--;
             }
-
             if(session->igmp_version == IGMP_VERSION_3) {
                 igmp.version = IGMP_VERSION_3;
                 igmp.type = IGMP_TYPE_REPORT_V3;
@@ -375,6 +374,15 @@ bbl_encode_packet_igmp (bbl_session_s *session)
                 }
                 break;
             }
+            if(group->state == IGMP_GROUP_JOINING) {
+                if(!group->robustness_count) {
+                    group->state = IGMP_GROUP_ACTIVE;
+                }
+            } else if(group->state == IGMP_GROUP_LEAVING) {
+                if(!group->robustness_count) {
+                    group->state = IGMP_GROUP_IDLE;
+                }
+            }
         }
     }
     if(!group) {