Yes, I purchased the double canopy umbrella in May at the PGA Superstore and used it the next day. Several weeks later I opened it to use again and one of the spokes had sheared off just at the point of the hinge. I just re-opened it again and discovered two additional spokes have sheared off at the same point. It is now completely unusable after 1 use on a single rainy day.
The umbrella has been in the back of my car and it has been quite hot - my best guess is that the plastic has deteriorated in the heat and become brittle.

I reached out to Titleist twice to let them know about this and inquire about warranty options, but they have not responded.

This happens based upon how you mount it to your bag...sometimes the "pinch" areas can be hard on umbrellas as well as the weather you are in such as high heat.

If you tried to reach them direct regarding a warranty issue, there might be a better way. If you had called them they most likely would have told you the following; if you purchased the product within the past year, you need to take the product back to the retailer where you purchased it with your receipt. Hope this helps. This has always helped me with any products.

Their Warranty -

Acushnet Company warrants its Titleist products for a period of one year from the date of purchase against defects in materials or workmanship. Should your Titleist product fail to perform for either of the above reasons, we will at our option, repair it or replace it with an equivalent product at no charge. To obtain the benefits of this warranty, please contact your local golf shop to set up a Return Authorization. If you need assistance locating a shop in your area, please visit the Titleist Golf Shop Locator. Enclose the original receipt along with an explanation of the defect in writing. We ask that all parts of the product be returned to the repair department and that the product remain in original factory condition. Warranty claims presented without the original sales slip will be reviewed at our sole discretion. Acushnet Company reserves the right to inspect all warranty claims to determine the extent of warranty applications. All products returned for warranty claims become the property of Acushnet Company.

Acushnet Company will not be liable for any consequential or other damages arising from the use of this product or any delay in the performance of this warranty due to causes beyond the company’s control. Some states do not allow the exclusion or limitation of incidental or consequential damages, so the above exclusion may not apply to you. This warranty gives you specific legal rights, and you may also have other rights which vary from state to state.