diff --git a/lib/solaar/cli/show.py b/lib/solaar/cli/show.py
index 3559193f..a516a76d 100644
--- a/lib/solaar/cli/show.py
+++ b/lib/solaar/cli/show.py
@@ -156,12 +156,21 @@ def _battery_json(battery):
     level = battery.level
     if isinstance(level, BatteryLevelApproximation):
         # A qualitative level (e.g. "good"), not an actual percentage
-        level_kind = "reported"
+        level_kind = "approximation"
     elif isinstance(level, int):
         level_kind = "level"
     else:
         level_kind = None
-    status = getattr(battery.status, "name", None)
+    status = getattr(battery.status, "name", None)  # canonical member name; combined flags have none on Python < 3.11
+    if status is None and battery.status is not None:
+        # Decompose combined flags into single-bit members so the output
+        # is identical on every Python version.
+        status = (
+            "|".join(
+                m.name for m in type(battery.status) if m.value and m.value & (m.value - 1) == 0 and (battery.status & m) == m
+            )
+            or None
+        )
     return {
         "level": int(level) if level is not None else None,
         "level_kind": level_kind,
@@ -184,7 +193,8 @@ def _receiver_json(receiver):
 
 def _device_json(dev):
     """Serialize a device as a JSON-friendly dict, or None if the device is gone."""
-    # Save the protocol before the ping, as it overrides it
+    # Save the descriptor-known protocol; the ping below may update it, and
+    # for an offline device the ping fails and would leave it unset.
     protocol = float(dev.protocol) if dev.protocol else None
     try:
         online = dev.ping()
@@ -201,7 +211,7 @@ def _device_json(dev):
         "name": dev.name,
         "number": dev.number,
         "receiver": _receiver_json(receiver),
-        "pid": dev.wpid or dev.product_id,
+        "pid": str(dev.wpid or dev.product_id),
         "path": dev.path,
         "bluetooth": dev.bluetooth,
         "mac": dev.hid_serial if dev.bluetooth else None,
@@ -562,9 +572,11 @@ def run(devices, args, find_receiver, find_device):
     assert args.device
 
     if args.json:
-        _json_output(devices, args.device.lower(), find_receiver, find_device)
-        for d in Device.instances:
-            d.close()
+        try:
+            _json_output(devices, args.device.lower(), find_receiver, find_device)
+        finally:
+            for d in Device.instances:
+                d.close()
         return
 
     print(f"{NAME.lower()} version {__version__}")
diff --git a/tests/solaar/cli/test_show_json.py b/tests/solaar/cli/test_show_json.py
index 46b8a619..8181d8d6 100644
--- a/tests/solaar/cli/test_show_json.py
+++ b/tests/solaar/cli/test_show_json.py
@@ -14,6 +14,8 @@
 ## with this program; if not, write to the Free Software Foundation, Inc.,
 ## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 
+from __future__ import annotations
+
 import json
 
 from dataclasses import dataclass
@@ -136,13 +138,13 @@ def test_battery_json_percentage():
 def test_battery_json_approximation():
     info = _battery_json(_battery(BatteryLevelApproximation.GOOD))
     assert info["level"] == 50
-    assert info["level_kind"] == "reported"
+    assert info["level_kind"] == "approximation"
 
 
 def test_battery_json_full_approximation():
     info = _battery_json(_battery(BatteryLevelApproximation.FULL, next_level=BatteryLevelApproximation.LOW))
     assert info["level"] == 90
-    assert info["level_kind"] == "reported"
+    assert info["level_kind"] == "approximation"
     assert info["next_level"] == 20
 
 
@@ -166,7 +168,7 @@ def test_battery_json_no_status():
 def test_battery_json_combined_status_flag():
     combined = BatteryStatus(0x07)  # bits from multiple flags (no canonical name on Python < 3.11)
     status = _battery_json(_battery(50, combined))["status"]
-    assert status is None or isinstance(status, str)
+    assert status == "RECHARGING|ALMOST_FULL|SLOW_RECHARGE"
 
 
 def test_receiver_json_none():
@@ -225,12 +227,12 @@ def test_device_json_bluetooth_device():
     assert info["online"] is True
 
 
-def test_device_json_reported_battery(mocker):
+def test_device_json_approximation_battery(mocker):
     dev = _keyboard_device()
     mocker.patch.object(dev, "battery", return_value=_battery(BatteryLevelApproximation.GOOD))
     info = _device_json(dev)
     assert info["battery"]["level"] == 50
-    assert info["battery"]["level_kind"] == "reported"
+    assert info["battery"]["level_kind"] == "approximation"
 
 
 def test_device_json_offline_battery_unavailable():
@@ -309,3 +311,18 @@ def test_run_json_output(mocker):
     output = _capture_json(mocker, run, [dev], args, None, None)
 
     assert [d["name"] for d in output["devices"]] == ["Craft Advanced Keyboard"]
+
+
+def test_run_json_closes_devices_when_output_raises(mocker):
+    from solaar.cli.show import Device
+    from solaar.cli.show import run
+
+    dev = _keyboard_device()
+    args = mocker.Mock(json=True, device="all")
+    mocker.patch("solaar.cli.show._json_output", side_effect=RuntimeError("boom"))
+    close = mocker.patch.object(Device, "close")
+
+    with pytest.raises(RuntimeError):
+        run([dev], args, None, None)
+
+    close.assert_called()