diff --git a/src/emu/ovni/mark.c b/src/emu/ovni/mark.c
index e887ae5..75314a1 100644
--- a/src/emu/ovni/mark.c
+++ b/src/emu/ovni/mark.c
@@ -311,6 +311,9 @@ create_thread_chan(struct ovni_mark_emu *m, struct bay *bay, struct thread *th)
 		struct chan *ch = &t->channels[i];
 		chan_init(ch, type->ctype, fmt, th->gindex, type->type);
 
+		/* Allow duplicates */
+		chan_prop_set(ch, CHAN_ALLOW_DUP, 1);
+
 		if (bay_register(bay, ch) != 0) {
 			err("bay_register failed");
 			return -1;
diff --git a/test/emu/ovni/libovni-mark.c b/test/emu/ovni/libovni-mark.c
index 21a6694..7f62346 100644
--- a/test/emu/ovni/libovni-mark.c
+++ b/test/emu/ovni/libovni-mark.c
@@ -63,6 +63,12 @@ main(void)
 		ovni_mark_set(MARK_PROGRESS, i);
 	}
 
+	/* Ensure we can emit the same value several times */
+	for (int i = 0; i < 10; i++) {
+		sleep_us(10);
+		ovni_mark_set(MARK_PROGRESS, 100);
+	}
+
 	instr_end();
 
 	return 0;