light brown patches on hosta leaves

 I have some light brown patches on my hosta leaves, mostly on Frances Williams. It almost looks like sunburn but it doesn't always face the sunny side. I thought frost in the spring but new patches have come up. There are not alot and they are not wet or gooy. I looked online under hosta diseases and nothing looked similar. Any ideas?

 I had brown patches on a couple of my hostas and was told it was because they got sunburn. I moved them to somewhere they didn't get full sun all day and they recovered. Might be worth trying.

How much sun do they get? If it's hot late afternoon sun that could be the problem. They are real shade lovers.