Hi! Thanks for your reply! My main 2 reasons for wanting to upgrade to 5.x are the new effects engine, and Android support. Plus, I generally like to stay up to date with updates/bug fixes when possible. I am currently running multiple (used) iPad 2 units for rehearsal and gigs for controlling Aux buses. Each musician gets to control their own mix. This is one of the best features of modern digital mixers (especially the DL series), in my opinion. As I understand it, if I update my DL1608 to the new firmware, I am then forced to update my iPad iOS versions, BUT, as I am sure you are aware, the problem is that the iPad 2 only supports a maximum of iOS version 9.3.5. Master Fader 5.x requires iOS version 11 or greater. I suppose if it's possible to update the DL1608 firmware but still use Master Fader 4 to control it, then it's not really an issue, but I don't think that's possible. I could be wrong. Feel free to correct me if this is the case. It really kind of ticks me off that I can't take advantage of the newer updates without completely replacing all my iPads with newer versions. I've been a software engineer for 30 years, so I understand the technical challenges that companies like Mackie and Apple face. Anyway, that's a whole other conversation. It is what it is. I just figure, this time, instead of forking out the cash for a set of (newer) used iPads (I'd go with the iPad Mini 2 this time), I could get a bunch of cheap used Android tablets. When I'm buying 5 or 6 tablets, it adds up. I could sell all my iPads and get enough money to buy the Androids. As of this writing, refurbished Fire HD 8 tablets are going for $54 on Amazon. But of course, I'm not sure which ones will work and which ones won't. In any case, I appreciate your input, and I will search again for the post you mentioned. I actually tried that before writing my original post, but I did not find a good answer. I could have missed it. I also had tried emailing Mackie support, but they never replied. What a surprise.