Hi
I have no idea about the genetics side of things but can confirm that blue eyes definitely don't mean that they are deaf, only selectively like all cockers!
Here are a couple of pictures of our little girl, when we first got her at 8 weeks you can see that she had really piercing blue eyes
This is her taken on the 24th December, not quite 4 months old and her eyes are now just very dark blue
She's still totally gorgeous whatever colour her eyes, hope you have as much fun and joy from your pup as this little lady has brought to us.
The blue you can see in those photos is not blue eyes as such, just light reflecting off the retina at the back of the eye. At certain angles and in certain lights, all dogs will have that.
Blue iris is another thing altogether. I don't think it is always associated with deafness. I think it is more likely to be if the fur is white also, but even then, not always.
I remember a COL member had a pup with one blue eye and one brown eye, but I think the blue one may have changed colour rather later than normal?
?
Can we see a photo of OP's blue eyed babe?