more pics

Dennis,

Sorry that no one has responded but disease issues can be difficult to address simply from photos. About the best we can do is suggest a bit more information or recommend that you contact your local state plant board or state Cooperative Extension Service; they can send plant samples to their Plant Disease Clinic for testing and recommendations.
Just from observation of the provided photos the symptoms may be the result of the below:

Bacterial leaf spot: Infections usually start at the leaf margins and can spread along the veins into the center of the leaf. Spots are brown and irregular and often appear as discrete spots with yellow halos.

Bacterial Soft Rot (Erwinia bacterium) typically begins in the mid to late growing season. It first develops near the base of the growing plant and slowly progresses downward into the underground rhizome. Badly infected stalks may actually topple over. The entire rhizome clump is often not totally infected but the rot progresses out towards the growing points as time allows. The entire clump may ultimately be affected but that is not the case for cultivars that seem to have some resistance. Cutting the canna stalk near the ground; appears to be pale brown instead of a healthy white color and it often extrudes a black gummy sap that is visible.

Rust; in your area at this time of the year it is a possibility but I donâÂÂt think that is your issue.

Virus: I do not see that at this time.

I suspect one of the first two listed is the problem. It might be helpful to know how you are watering. Overhead sprinkling late in the day does not allow time for the foliage to dry and can be an issue with Bacterial Leaf Spot. Water drops splatter soil onto the lower leaves and this typically causes the problem.

Kent