diff --git a/src/public/javascripts/services/ws.js b/src/public/javascripts/services/ws.js
index 315c31a33..c258fd2db 100644
--- a/src/public/javascripts/services/ws.js
+++ b/src/public/javascripts/services/ws.js
@@ -106,7 +106,7 @@ function checkSyncIdListeners() {
         .filter(l => l.desiredSyncId > lastSyncId);
 
     syncIdReachedListeners.filter(l => Date.now() > l.start - 60000)
-        .forEach(l => console.log(`Waiting for syncId ${l.desiredSyncId} while current is ${lastSyncId} for ${Date.now() - l.start}`));
+        .forEach(l => console.log(`Waiting for syncId ${l.desiredSyncId} while current is ${lastSyncId} for ${Math.floor((Date.now() - l.start) / 1000)}s`));
 }
 
 async function consumeSyncData() {
diff --git a/src/services/ws.js b/src/services/ws.js
index de7c92ae6..7661afca5 100644
--- a/src/services/ws.js
+++ b/src/services/ws.js
@@ -5,7 +5,6 @@ const sql = require('./sql');
 const syncMutexService = require('./sync_mutex');
 
 let webSocketServer;
-let lastSyncId = 0;
 
 function init(httpServer, sessionParser) {
     webSocketServer = new WebSocket.Server({
@@ -29,13 +28,11 @@ function init(httpServer, sessionParser) {
         ws.on('message', messageJson => {
             const message = JSON.parse(messageJson);
 
-            lastSyncId = Math.max(lastSyncId, message.lastSyncId);
-
             if (message.type === 'log-error') {
                 log.error('JS Error: ' + message.error);
             }
             else if (message.type === 'ping') {
-                syncMutexService.doExclusively(async () => await sendPing(ws, lastSyncId));
+                syncMutexService.doExclusively(async () => await sendPing(ws, message.lastSyncId));
             }
             else {
                 log.error('Unrecognized message: ');