diff --git a/node-binance-api.js b/node-binance-api.js
index <HASH>..<HASH> 100644
--- a/node-binance-api.js
+++ b/node-binance-api.js
@@ -708,7 +708,7 @@ module.exports = function() {
         // This now conforms 100% to the Binance docs constraints on managing a local order book
         if ( context.lastEventUpdateId ) {
             const expectedUpdateId = context.lastEventUpdateId + 1;
-            if ( depth.U === expectedUpdateId ) {
+            if ( depth.U <= expectedUpdateId ) {
                 updateDepthCache();
             } else {
                 let msg = 'depthHandler: ['+symbol+'] The depth cache is out of sync.';
Relax depthCache out of sync check

It is possible that the exchange will send a range of depth updates, a subset, at the start, of which we have already cached. This should be allowed by the out of sync check.

The out of sync check will now only treat a gap between the cached data, and newly received data as truly out of sync.

Thanks @learnathoner