This issue is not fixed. I tried all of the things you suggest here last week and nothing worked. I've seen this issue mentioned numerous times around the internet regarding the Roku Ultra Pro rechargeable remote and your answer is the one that always is given and it doesn't seem to work for anyone. I've come to the conclusion that this is just a bad product so have ordered a basic remote to replace it. It's a shame that I can't get product support or reimbursement for a product that is only a few months old.
You never use the pairing buttons to program your tv volume to ANY Roku remote. The pairing buttons is only there to get the Roku remote controlling the Roku itself. So, if it stopped controlling your tv volume you have to reprogram it for your tv brand.
settings> remote & devices> remote> remote in USE> program tv> follow prompts.
