Balance problems caused by pain patch?

My husband was diagnosed with PD in early 2023, but we think he's had it for 7 years but doctors kept saying other things. Now he has Dropped Head Syndrome and been prescribed opioid pain patch for his neck pain, Buprenorphine 5mcg per hour. Three weeks later he has serious balance problems almost all day. He's been doing well on Carbidopa Levadopa for months. Has anyone else had similar problems? Thank you.