diff --git a/case-lib/config.sh b/case-lib/config.sh
index c07e9864..1479b0a5 100644
--- a/case-lib/config.sh
+++ b/case-lib/config.sh
@@ -19,11 +19,6 @@ declare -A TPLG_IGNORE_LST
 # shellcheck disable=SC2034
 TPLG_IGNORE_LST['pcm']='HDA Digital'
 
-# Will be set by the lib function, don't need to set
-# Catches the last line of /var/log/kern.log, which will be used by
-#   sof-kernel-log-check.
-# KERNEL_CHECKPOINT
-
 # If not set will be automatically set by logging_ctl function
 # Test case log root
 # EXAMPLE: the log for test-case/check-ipc-flood.sh will be stored at
@@ -63,7 +58,15 @@ SUDO_LEVEL=${SUDO_LEVEL:-}
 #
 # NO_BT_MODE=true
 
-# Test interval between two test cases, the default value is 5 seconds
-# in CI, which is controlled by sof-framework. In manual run, user can
-# override the default value.
+# SOF_TEST_INTERVAL informs sof-test of how long the external test
+# runner waits between the end of one sof-test and the start of the next
+# sof-test. sof-test uses this value to assign the corresponding kernel
+# logs "no man's land" to the second test, which can be confusing (see
+# for instance https://github.com/thesofproject/sof/issues/5032) but
+# safer: it makes sure no kernel error escapes.
+# See initial review in https://github.com/thesofproject/sof-test/pull/639
+#
+# The default value must be 5s because 5s is the inter-test delay
+# waited by the internal test runner used by sof/jenkins CI and that
+# test runner does not define SOF_TEST_INTERVAL (internal bug 158)
 SOF_TEST_INTERVAL=${SOF_TEST_INTERVAL:-5}
diff --git a/case-lib/lib.sh b/case-lib/lib.sh
index 7c30b7ce..d7bc0075 100644
--- a/case-lib/lib.sh
+++ b/case-lib/lib.sh
@@ -42,9 +42,12 @@ fi
 
 setup_kernel_check_point()
 {
-    # Make the check point $SOF_TEST_INTERVAL second(s) earlier to avoid log loss.
-    # Note this may lead to an error caused by one test appear in the next one.
-    KERNEL_CHECKPOINT=$(($(date +%s) - SOF_TEST_INTERVAL))
+    # Make the check point $SOF_TEST_INTERVAL second(s) earlier to avoid
+    # log loss.  Note this may lead to an error caused by one test
+    # appear in the next one, see comments in config.sh.  Add 3 extra
+    # second to account for our own, sof-test delays after PASS/FAIL
+    # decision: time spent collecting logs etc.
+    KERNEL_CHECKPOINT=$(($(date +%s) - SOF_TEST_INTERVAL - 3))
 }
 
 # This function adds a fake error to dmesg (which is always saved by
diff --git a/test-case/run-all-tests.sh b/test-case/run-all-tests.sh
index 000ab3be..15aa9beb 100755
--- a/test-case/run-all-tests.sh
+++ b/test-case/run-all-tests.sh
@@ -95,7 +95,9 @@ main()
 	while getopts "l:T:xh" OPTION; do
 	case "$OPTION" in
 		l) tests_length="$OPTARG" ;;
-		T) time_delay="$OPTARG" ;;
+		T) time_delay="$OPTARG"
+		   export SOF_TEST_INTERVAL="$OPTARG"
+		   ;;
 		x) exit_first=true ;;
 		*) usage; exit 1 ;;
 		esac