HR20-700 Remote Sluggish Most of the Time

I have the HR20-700 and the RC-34 remote is VERY slow to respond most times, but it can be intermittent. When it is slow we will type numbers and it will take several seconds for them to register, so you retype them thinking it didn't take and you get the wrong channel. This can go on for almost 30 seconds before you hit the right channel and can get very frustrating. Similarly when you go into the guide and press up/down, that is slow as well, usually 1-4 seconds for it to register. We watch TV mostly between 6pm-10pm during the week and during that time it is almost always slow. At other times it can be relatively quick with less than 1 second of lag. I've had the HR20 since shortly after they came out and initially it seemed that things would be slow like this after an update, but then a future update would usually fix the issue and it would only be slow maybe 20% of the time. Lately the slowness seems to happen about 80% of the time and works as you would expect only about 20%. I use the remote on RF mode and tried switching it to IR just for kicks, but that help at all. We've also fully charged the batteries and get the same thing. Any suggestions are appreciated. Thanks