EDIT: to be clear, this is ONLY for THR10 and THR5, not for any of the new THRs with letter designations. Those of you who have purchased the older version of these amps now have the option to update the firmware and upgrade your amp! This is now the THR5/10 V2. I have just done it and the change is quite pronounced. I'll try my best to outline it, as I know there are a few of you that have these wee beasties. But first, here's how: Yamaha Downloads Select your country, then type in your amp model. This should give the option to select THR V2, or in the list of downloads you'll see an update package that mentions V2. Click and follow the instructions to download. The extract the files, doesn't matter where, and run the setup. An instruction manual also comes with the package that you download. Read the manual and follow the instructions. Don't know what version your THR is running? To check that mine was running version 2 I had to run through a step which I assume would be the same for any version check. Turn the amp on whilst holding down the Tap:Time button. The display should then show which version you are running, which in my case came out as 2_0_0, whic scrolls across the screen in succession. So what does it do? It's supposed to have better speaker IR's and Cleaner cleans and dirtier dirts. I can attest that the dirt channels are a lot more usable without having to have my tone knob parked over the three quarters mark. Sounds a bit tighter too, and perhaps even a bit more tubey and authentic. The biggest change, however, is in the clean channel. I'm not entirely sold on this change; I used to enjoy the rich warmth of clean channel, whereas now it sounds more like my Vox cleans - jangly and bright. It's allegedly the same clean channel that's on the THR10C. I'll need to play with it more to get more of a handle on it, but minus the change to the clean channel I'm liking it. Even with that I would say it's worth it. I'm not sure if it'll mess up any of your presets. I hope you THR owners find this useful!