Math.NET CryptoRandomSource Next is Biased

I am developing a gaming platform that is subject to heavy regulatory scrutiny. I chose Math.NET because it seemed like a good fit. However I have just received this comment back from our auditors.

Comments please if this is accurate and how it can be resolved?

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In RandomSource(), Next(int, int) is defined as follows:

    public override sealed int Next(int minValue, int maxValue)
    {
        if (minValue > maxValue)
        {
            throw new ArgumentException(Resources.ArgumentMinValueGreaterThanMaxValue);
        }

        if (_threadSafe)
        {
            lock (_lock)
            {
                return (int)(DoSample()*(maxValue - minValue)) + minValue;
            }
        }

        return (int)(DoSample()*(maxValue - minValue)) + minValue;
    }

This creates a bias in the same way as before. Using an un-scaled value from the RNG and multiplying it by the range without previously eliminating the bias (unless the range is a power of 2, there will be a bias ).