Can someone help me with the conversion I am facing in enclosed code ... I commented the lines of code, where I am having problem. Is this even the right way to achieve this ... what I am trying to do, is forward responses of specified type to provided callback.

public class MessageBinder
{
    private class Subscriber<T> : IEquatable<Subscriber<T>> where T : Response
    {
        ...
    }

    private readonly Dictionary<Type, List<Subscriber<Response>>> bindings;

    public MessageBinder()
    {
        this.bindings = new Dictionary<Type, List<Subscriber<Response>>>();
    }

    public void Bind<TResponse>(short shortAddress, Action<ZigbeeAsyncResponse<TResponse>> callback)
        where TResponse : Response
    {
        List<Subscriber<TResponse>> subscribers = this.GetSubscribers<TResponse>();
        if (subscribers != null)
        {
            subscribers.Add(new Subscriber<TResponse>(shortAddress, callback));
        }
        else
        {
            var subscriber = new Subscriber<TResponse>(shortAddress, callback);

            // ERROR: cannot convert from 'List<Subscriber<TResponse>>' to 'List<Subscriber<Response>>' ... tried LINQ Cast operator - does not work either
            this.bindings.Add(typeof(TResponse), new List<Subscriber<TResponse>> { subscriber });
        }
    }

    public void Forward<TResponse>(TResponse response)
        where TResponse : Response
    {
        var subscribers = this.GetSubscribers<TResponse>();
        if (subscribers != null)
        {
            Subscriber<TResponse> subscriber;
            Type responseType = typeof (TResponse);

            if (responseType.IsSubclassOf(typeof (AFResponse)))
            {
                // ERROR: Cannot convert type 'TResponse' to 'AFResponse' ... tried cast to object first, works, but is this the right way?
                var afResponse = (AFResponse)response;
                subscriber = subscribers.SingleOrDefault(s => s.ShortAddress == afResponse.ShortAddress);
            }
            else
            {
                subscriber = subscribers.First();
            }

            if (subscriber != null)
            {
                subscriber.Forward(response);
            }
        }
    }

    private List<Subscriber<TResponse>> GetSubscribers<TResponse>() where TResponse : Response
    {
        List<Subscriber<Response>> subscribers;
        this.bindings.TryGetValue(typeof(TResponse), out subscribers);

        // ERROR: How can I cast List<Subscriber<Response>> to List<Subscriber<TResponse>>?
        return subscribers;
    }
}

Thank you for any help :)