diff --git a/README.md b/README.md
index 6e16ecc42..9032936e5 100644
--- a/README.md
+++ b/README.md
@@ -50,6 +50,7 @@ Since v5.5.0 of the JavaScript adapter the following locations (relative to the
 
 * (klein0r) Day of week as number always returns 1 (monday) to 7 (sunday)
 * (klein0r) Fixed layout of script type selection
+* (klein0r) Fixed sendto with multiple instances (for callback / timeout handling)
 
 ### 7.4.0 (2023-12-08)
 
diff --git a/lib/sandbox.js b/lib/sandbox.js
index 9d75eea67..2924737ba 100644
--- a/lib/sandbox.js
+++ b/lib/sandbox.js
@@ -2713,28 +2713,59 @@ function sandBox(script, name, verbose, debug, context) {
                         try {
                             callback.call(sandbox, {error: 'timeout'}, options, _adapter);
                         } catch (e) {
-                            errorInCallback(e); //adapter.log.error('Error in callback: ' + e)
+                            errorInCallback(e);
                         }
                         callback = null;
                     }
                 }, timeoutDuration);
             }
 
-            sandbox.verbose && sandbox.log(`sendTo(adapter=${_adapter}, cmd=${cmd}, msg=${JSON.stringify(msg)})`, 'info');
-            adapter.sendTo(_adapter, cmd, msg, timeout && function (result) {
-                timeout && clearTimeout(timeout);
+            // If specific instance
+            if (_adapter.match(/\.[0-9]+$/)) {
+                sandbox.verbose && sandbox.log(`sendTo(instance=${_adapter}, cmd=${cmd}, msg=${JSON.stringify(msg)}, hasCallback=${typeof callback === 'function'})`, 'info');
+                adapter.sendTo(_adapter, cmd, msg, timeout && function (result) {
+                    timeout && clearTimeout(timeout);
 
-                sandbox.verbose && result && sandbox.log(`sendTo => ${JSON.stringify(result)}`, 'debug');
+                    sandbox.verbose && result && sandbox.log(`sendTo => ${JSON.stringify(result)}`, 'debug');
 
-                if (typeof callback === 'function') {
-                    try {
-                        callback.call(sandbox, result, options, _adapter);
-                    } catch (e) {
-                        errorInCallback(e); //adapter.log.error('Error in callback: ' + e)
+                    if (typeof callback === 'function') {
+                        try {
+                            callback.call(sandbox, result, options, _adapter);
+                        } catch (e) {
+                            errorInCallback(e);
+                        }
+                        callback = null;
                     }
-                    callback = null;
-                }
-            }, options);
+                }, options);
+            } else {
+                // Send to all instances
+                context.adapter.getObjectView('system', 'instance', {startkey: `system.adapter.${_adapter}.`, endkey: `system.adapter.${_adapter}.\u9999`}, options, (err, res) => {
+                    if (err || !res) {
+                        sandbox.log(`sendTo failed: ${err.message}`, 'error');
+                        return;
+                    }
+
+                    const instances = res.rows.map(item => item.id.substring('system.adapter.'.length));
+
+                    instances.forEach(instance => {
+                        sandbox.verbose && sandbox.log(`sendTo(instance=${instance}, cmd=${cmd}, msg=${JSON.stringify(msg)}, hasCallback=${typeof callback === 'function'})`, 'info');
+                        adapter.sendTo(instance, cmd, msg, timeout && function (result) {
+                            timeout && clearTimeout(timeout);
+
+                            sandbox.verbose && result && sandbox.log(`sendTo => ${JSON.stringify(result)}`, 'debug');
+
+                            if (typeof callback === 'function') {
+                                try {
+                                    callback.call(sandbox, result, options, instance);
+                                } catch (e) {
+                                    errorInCallback(e);
+                                }
+                                callback = null;
+                            }
+                        }, options);
+                    });
+                });
+            }
         },
         sendto: function (_adapter, cmd, msg, callback) {
             return sandbox.sendTo(_adapter, cmd, msg, callback);
@@ -3324,9 +3355,8 @@ function sandBox(script, name, verbose, debug, context) {
                 }
                 return;
             }
-            let timeout = setTimeout(() => {
-                timeout = null;
 
+            const timeout = setTimeout(() => {
                 sandbox.verbose && sandbox.log('getHistory => timeout', 'debug');
 
                 if (typeof callback === 'function') {