diff --git a/java-agent/src/jvmMain/kotlin/com/epam/drill/agent/test/sending/TestInfoSender.kt b/java-agent/src/jvmMain/kotlin/com/epam/drill/agent/test/sending/TestInfoSender.kt
index b3db15bc3..20634f2a4 100644
--- a/java-agent/src/jvmMain/kotlin/com/epam/drill/agent/test/sending/TestInfoSender.kt
+++ b/java-agent/src/jvmMain/kotlin/com/epam/drill/agent/test/sending/TestInfoSender.kt
@@ -49,13 +49,13 @@ class IntervalTestInfoSender(
     }
 
     override fun stopSendingTests() {
+        sendTests(collectTests())
+        messageSender.shutdown()
         scheduledThreadPool.shutdown()
         if (!scheduledThreadPool.awaitTermination(1, TimeUnit.SECONDS)) {
             logger.error("Failed to send some tests prior to shutdown")
             scheduledThreadPool.shutdownNow();
         }
-        sendTests(collectTests())
-        messageSender.shutdown()
         logger.info { "Test sending job is stopped." }
     }
 
diff --git a/lib-jvm-shared/agent-transport/src/jvmMain/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSender.kt b/lib-jvm-shared/agent-transport/src/jvmMain/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSender.kt
index b69962d01..01b1930a8 100644
--- a/lib-jvm-shared/agent-transport/src/jvmMain/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSender.kt
+++ b/lib-jvm-shared/agent-transport/src/jvmMain/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSender.kt
@@ -16,7 +16,6 @@
 package com.epam.drill.agent.transport
 
 import mu.KotlinLogging
-import com.epam.drill.agent.common.transport.AgentMessage
 import com.epam.drill.agent.common.transport.AgentMessageDestination
 import com.epam.drill.agent.common.transport.AgentMessageSender
 import kotlinx.serialization.KSerializer
@@ -52,7 +51,7 @@ open class QueuedAgentMessageSender(
         }
     }
 
-    override fun <T>send(destination: AgentMessageDestination, message: T, serializer: KSerializer<T>) {
+    override fun <T> send(destination: AgentMessageDestination, message: T, serializer: KSerializer<T>) {
         val mappedDestination = destinationMapper.map(destination)
         val serializedMessage = messageSerializer.serialize(message, serializer)
         if (!isRunning.get()) {
@@ -69,10 +68,10 @@ open class QueuedAgentMessageSender(
     }
 
     override fun shutdown() {
-        isRunning.set(false)
+        if (!isRunning.compareAndSet(true, false)) return
         executor.shutdown()
         try {
-            if (!executor.awaitTermination(5, TimeUnit.SECONDS)) {
+            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {
                 executor.shutdownNow()
             }
         } catch (e: InterruptedException) {
@@ -144,6 +143,7 @@ open class QueuedAgentMessageSender(
                 tryToSend(destination, message) || handleUnsent(destination, message, reason)
             }
         } while (message != null)
+        logger.info { "Finished unloading a message queue." }
     }
 
     /**
diff --git a/lib-jvm-shared/agent-transport/src/jvmTest/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSenderTest.kt b/lib-jvm-shared/agent-transport/src/jvmTest/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSenderTest.kt
index 5169a4ef6..97b664534 100644
--- a/lib-jvm-shared/agent-transport/src/jvmTest/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSenderTest.kt
+++ b/lib-jvm-shared/agent-transport/src/jvmTest/kotlin/com/epam/drill/agent/transport/QueuedAgentMessageSenderTest.kt
@@ -180,10 +180,10 @@ class QueuedAgentMessageSenderTest {
         calls?.waitFor { verify(exactly = it) { messageSerializer.serialize(any(), TestAgentMessage.serializer()) } }
         calls?.waitFor { verify(exactly = it) { destinationMapper.map(any()) } }
         enqueued?.waitFor {
-            assertEquals(it, queueOffers.filter { o -> o }.size)
+            assertEquals(it, queueOffers.filter { o -> o }.size, "Expected $it messages to be enqueued, but was ${queueOffers.filter { o -> o }.size}")
         }
         dequeued?.waitFor {
-            assertEquals(it, queuePolls.filterNotNull().size)
+            assertEquals(it, queuePolls.filterNotNull().size, "Expected $it messages to be dequeued, but was ${queuePolls.filterNotNull().size}")
         }
 
         sendingAttempts?.waitFor { verify(exactly = it) { messageTransport.send(any(), any(), any()) } }
@@ -191,7 +191,7 @@ class QueuedAgentMessageSenderTest {
         unsent?.waitFor { verify(exactly = it) { messageSendingListener.onUnsent(any(), any()) } }
     }
 
-    private fun <T> T.waitFor(timeout: Long = 1000, block: (T) -> Unit) {
+    private fun <T> T.waitFor(timeout: Long = 2000, block: (T) -> Unit) {
         val start = System.currentTimeMillis()
         val timeIsOut = { System.currentTimeMillis() - start > timeout }
         var error: Throwable? = null
diff --git a/test2code/src/main/kotlin/com/epam/drill/agent/test2code/coverage/CoverageSender.kt b/test2code/src/main/kotlin/com/epam/drill/agent/test2code/coverage/CoverageSender.kt
index 8fec6feb2..edad511ac 100644
--- a/test2code/src/main/kotlin/com/epam/drill/agent/test2code/coverage/CoverageSender.kt
+++ b/test2code/src/main/kotlin/com/epam/drill/agent/test2code/coverage/CoverageSender.kt
@@ -59,14 +59,14 @@ class IntervalCoverageSender(
     }
 
     override fun stopSendingCoverage() {
+        sendProbes(collectReleasedProbes())
+        sendProbes(collectUnreleasedProbes())
+        sender.shutdown()
         scheduledThreadPool.shutdown()
-        if (!scheduledThreadPool.awaitTermination(5, TimeUnit.SECONDS)) {
+        if (!scheduledThreadPool.awaitTermination(1, TimeUnit.SECONDS)) {
             logger.error("Failed to send some coverage data prior to shutdown")
             scheduledThreadPool.shutdownNow();
         }
-        sendProbes(collectReleasedProbes())
-        sendProbes(collectUnreleasedProbes())
-        sender.shutdown()
         logger.info { "Coverage sending job is stopped." }
     }
 
diff --git a/test2code/src/test/kotlin/com/epam/drill/agent/test2code/classparsing/ChecksumTest.kt b/test2code/src/test/kotlin/com/epam/drill/agent/test2code/classparsing/ChecksumTest.kt
index c37d25c19..0b7d74f1e 100644
--- a/test2code/src/test/kotlin/com/epam/drill/agent/test2code/classparsing/ChecksumTest.kt
+++ b/test2code/src/test/kotlin/com/epam/drill/agent/test2code/classparsing/ChecksumTest.kt
@@ -50,8 +50,10 @@ class ChecksumTest {
 
     @Test
     fun `changing lambda body should change it's checksum`() {
-        val methodSignatureBuild1 = "com/epam/drill/agent/fixture/ast/Build1:lambda\$null\$2:java.lang.String:java.lang.String"
-        val methodSignatureBuild2 = "com/epam/drill/agent/fixture/ast/Build2:lambda\$null\$2:java.lang.String:java.lang.String"
+        val methodSignatureBuild1 =
+            "com/epam/drill/agent/fixture/ast/Build1:lambda\$theSameMethodBody$0:java.lang.String:java.lang.String"
+        val methodSignatureBuild2 =
+            "com/epam/drill/agent/fixture/ast/Build2:lambda\$theSameMethodBody$0:java.lang.String:java.lang.String"
         assertNotEquals(
             checksumsBuild1[methodSignatureBuild1],
             checksumsBuild2[methodSignatureBuild2]