My dog sounds like she is congested, almost like Darth Vadar.?

Has anyone had this with their dog? My dog has epilespy and has to take phenobarbital and potium bromide. I'm not sure if the meds have anything to do with it. I told the vet about it last time she had her blood work and she didn't seem concerned. She isn't gagging, having a hard time breathing, coughing or vomiting, but she sounds like she almost has a sore throat (without pain). Any ideas?