I just sent them an email last night. Here is the reply I received from them this morning.
Thank you for contacting Sprint. I understand your concern regarding your HTC 6800 phone and it is not working properly.
I have discussed your case with my supervisor and I am happy to inform you that the phone can be replaced for you.
Please visit the nearest Sprint Store to purchase the new phone of your choice and our store representative will be glad to assist you in choosing a new phone, as per your requirements.
Just click on this hyperlink to find the nearest Sprint Store in your
vicinity:
http://storelocator.sprint.com
Please swap your current phone with the new phone by contacting us at
1-888-211-4727 from a landline phone.
Once you activate the new phone, please reply to this email with a scanned copy of your purchase receipt of new phone and we will send a return kit for the HTC 6800 phone.
Once we receive the HTC 6800 phone, we will apply the credit of $549.99 equal to the cost of the HTC 6800 phone to your account. So you will not be charged for the replacement phone.
I have placed a supporting note on your account in this regard.
Your satisfaction as a Sprint subscriber is important to us. If there is anything else I can assist you with, please reply.
Thank you for writing to us. Have a great day!
Sincerely,
James B.
Sprint