Synchronize on BT routes map to avoid ConcurrentModificationException

                .getBluetoothRoutes();

        List<Pair<AudioRoute, BluetoothDevice>> btRoutesToRemove =

                new ArrayList<>();

        // Prevent concurrent modification exception by just iterating

        //through keys instead of simultaneously removing them. Ensure that

        // we synchronize on the map while we traverse via an Iterator.

        synchronized (btRoutes) {

            for (AudioRoute route: btRoutes.keySet()) {

                if (route.getType() != PROFILE_TO_AUDIO_ROUTE_MAP.get(profile)) {

                    continue;

                }

                BluetoothDevice device = btRoutes.get(route);

            // Prevent concurrent modification exception by just iterating through keys instead of

            // simultaneously removing them.

                btRoutesToRemove.add(new Pair<>(route, device));

            }

        }

        for (Pair<AudioRoute, BluetoothDevice> routeToRemove:

                btRoutesToRemove) {