diff --git a/libs/main/io_utils/piconnection.cpp b/libs/main/io_utils/piconnection.cpp
index 2e0e407f..50f6e565 100644
--- a/libs/main/io_utils/piconnection.cpp
+++ b/libs/main/io_utils/piconnection.cpp
@@ -1000,6 +1000,7 @@ PIIODevice * PIConnection::DevicePool::addDevice(PIConnection * parent, const PI
 	if (pmode == mode || pmode == PIIODevice::ReadWrite) return dd->dev;
 	if ((mode & PIIODevice::ReadOnly) > 0) {
 		if (dd->rthread) {
+			dd->rthread->stopAndWait();
 			delete dd->rthread;
 			dd->rthread = nullptr;
 			dd->started = false;