Similar to #336 issue we have the producer trying to wakeup the consumer after a fill here:

    private void wakeupConsumer()
    {
        Thread consumerThread;
        do
        {
            consumerThread = lvBlocked();
        } while (consumerThread == null);

        LockSupport.unpark(consumerThread);
    }

The consumer can wake up from a timeout independently during the time period between the 'fill' moving the producerIndex and the wakeup call. The producer thread then spins as it cannot find a blocked consumer.