Exact same problem. I wish Roku Would actually answer this question instead of asking everyone to DM their serial number and account email address to them. It seems this forum would be better if Roku would actually answer the question or tell people what might be wrong with the design so we would know why the batteries keep draining.
Please send me a PM with your Roku account email address, and include the serial number of the Roku device from Settings>System>About along with a summary of the issue you are experiencing. I'll be able to assist you further from there.
Recently my Roku Ultra point anywhere remote was dead so naturally I thought to just replace the batteries. Well I do and it will control the Roku and TV for about 5 seconds, flash that the batteries are dead, then have no control at all. I have tried with multiple sets of new batteries and can confirm that they have an adequate charge. Every time I take out and reinsert the batteries, I gain control for a few seconds then loose it. I did do some network changes recently but I can't see how mounting the AP in the living room vs leaving it on the office floor would make a difference but maybe it did.
I just received the new enhanced remote on 9/17, that was on back order for several weeks, which did not come with batteries. I purchased brand new batteries and they have already drained after less than four days, with regular use- no private listening. I reviewed other similar posts and the solution on each was to send a private message, but I do not have that option without posting my own message. I recently purchased the Roku speakers that came with two remote, but neither have the enhanced features, so I paid an additional 29.99 for a fourth remote, just to have it die on the fourth day. The ability to contact Roku support continues to be so frustrating and difficult, especially when so many others have the same problem but you don’t post a solution that helps everyone.