diff --git a/src/libsystemd/sd-bus/bus-dump-json.c b/src/libsystemd/sd-bus/bus-dump-json.c
index 8238ac587e..ae3e806194 100644
--- a/src/libsystemd/sd-bus/bus-dump-json.c
+++ b/src/libsystemd/sd-bus/bus-dump-json.c
@@ -72,6 +72,7 @@ static int json_transform_dict_array(sd_bus_message *m, sd_json_variant **ret) {
         CLEANUP_ARRAY(elements, n_elements, sd_json_variant_unref_many);
 
         for (;;) {
+                _cleanup_(sd_json_variant_unrefp) sd_json_variant *key = NULL;
                 const char *contents;
                 char type;
 
@@ -94,11 +95,35 @@ static int json_transform_dict_array(sd_bus_message *m, sd_json_variant **ret) {
                 if (r < 0)
                         return r;
 
-                r = json_transform_one(m, elements + n_elements);
+                r = json_transform_one(m, &key);
                 if (r < 0)
                         return r;
 
-                n_elements++;
+                /* JSON only supports string keys in objects, but D-Bus specification is a bit more lenient
+                 * and allows dict entries to have any basic type as key. Let's stringify allowed non-string
+                 * keys so that we can represent them as JSON objects. */
+                if (!sd_json_variant_is_string(key)) {
+                        _cleanup_free_ char *s = NULL;
+
+                        if (!IN_SET(sd_json_variant_type(key),
+                                    SD_JSON_VARIANT_BOOLEAN,
+                                    SD_JSON_VARIANT_INTEGER,
+                                    SD_JSON_VARIANT_REAL,
+                                    SD_JSON_VARIANT_UNSIGNED))
+                                return -EINVAL;
+
+                        r = sd_json_variant_format(key, /* flags= */ 0, &s);
+                        if (r < 0)
+                                return r;
+
+                        key = sd_json_variant_unref(key);
+
+                        r = sd_json_variant_new_string(&key, s);
+                        if (r < 0)
+                                return r;
+                }
+
+                elements[n_elements++] = TAKE_PTR(key);
 
                 r = json_transform_one(m, elements + n_elements);
                 if (r < 0)
diff --git a/test/units/TEST-74-AUX-UTILS.busctl.sh b/test/units/TEST-74-AUX-UTILS.busctl.sh
index 875f353b00..54170cf5b5 100755
--- a/test/units/TEST-74-AUX-UTILS.busctl.sh
+++ b/test/units/TEST-74-AUX-UTILS.busctl.sh
@@ -43,6 +43,12 @@ busctl call --json=short \
 busctl call -j \
             org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.DBus.Properties \
             GetAll s "org.freedesktop.systemd1.Manager" | jq -c
+# Do the same with D-Bus' org.freedesktop.DBus.Debug.Stats interface which also provides some
+# complex signatures that caused issues during the JSON conversion in the past
+# See: https://github.com/systemd/systemd/issues/32904
+busctl call --json=pretty \
+            org.freedesktop.DBus /org/freedesktop/DBus org.freedesktop.DBus.Debug.Stats \
+            GetStats | jq -c
 busctl call --verbose --timeout=60 --expect-reply=yes \
             org.freedesktop.systemd1 /org/freedesktop/systemd1 org.freedesktop.systemd1.Manager \
             ListUnitsByPatterns asas 1 "active" 2 "systemd-*.socket" "*.mount"