diff --git a/CMakeLists.txt b/CMakeLists.txt
index c4363d2..6f8402b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -12,7 +12,7 @@ if ("x${CMAKE_MODULE_PATH}" STREQUAL "x")
 	set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 endif()
 
-find_package(PIP REQUIRED)
+find_package(PIP 4.0 REQUIRED)
 find_package(QAD)
 include(SHSTKMacros)
 shstk_begin_project(CD)
diff --git a/libs/core/cdutils_core.cpp b/libs/core/cdutils_core.cpp
index e51f6cb..e546c54 100644
--- a/libs/core/cdutils_core.cpp
+++ b/libs/core/cdutils_core.cpp
@@ -4,6 +4,7 @@
 #include "piconfig.h"
 #include "piiobytearray.h"
 #include "piiostring.h"
+#include "piliterals_time.h"
 
 using namespace CDUtils;
 
@@ -90,10 +91,10 @@ CDCore::CDCore() {
 
 
 CDCore::~CDCore() {
-	x_timer.stop();
+	x_timer.stopAndWait();
 	datatr.stop();
 	sendt.stop();
-	sendt.waitForFinish(10);
+	sendt.waitForFinish(100_ms);
 	connection.stop();
 }
 
@@ -213,7 +214,7 @@ void CDCore::init(const PIString & configuration, bool pult) {
 
 
 void CDCore::stop() {
-	x_timer.stop();
+	x_timer.stopAndWait();
 	connection.stop();
 }
 
@@ -226,12 +227,12 @@ void CDCore::release() {
 
 void CDCore::startX(double freq) {
 	// piCout << "start x" << x_timer.isRunning() << freq;
-	if (!x_timer.isRunning()) x_timer.start(1000. / piMaxd(freq, 0.01));
+	if (!x_timer.isRunning()) x_timer.start(piMax(PISystemTime::Frequency::fromHertz(freq), 0.01_Hz));
 }
 
 
 void CDCore::stopX() {
-	x_timer.stop();
+	x_timer.stopAndWait();
 }
 
 
diff --git a/libs/core/cdutilstest.cpp b/libs/core/cdutilstest.cpp
index 99ec397..69eb32e 100644
--- a/libs/core/cdutilstest.cpp
+++ b/libs/core/cdutilstest.cpp
@@ -5,6 +5,7 @@
 #include "cdutils_m.h"
 #include "cdutils_x.h"
 #include "k_description.h"
+#include "piliterals_time.h"
 #include "pip.h"
 
 using namespace CDUtils;
@@ -68,7 +69,7 @@ public:
 	}
 	EVENT_HANDLER(void, xrecv) {
 		piCout << "received x";
-		if (!timer.isRunning()) timer.start(10);
+		if (!timer.isRunning()) timer.start(100_Hz);
 		X.start();
 	}
 	EVENT_HANDLER(void, timerDone) { test(); }