The bassett is not aggressive at all and I think sees it as play, but occasionally when the bassett reacts playfully it intensifies to heavier snarling/growling, and when the bassett plays and puts the beagle down or on back, it intensifies. I just read what's below on the training forum and may try that if it stays constant. It has been constant, every time the bassett moves away or runs toward something else, she goes for the back.
If she does anything you consider rude or unacceptable when playing with the others (jumping on them, biting, barking, mouthing...whatever you decide is too much), show her it's not okay by taking away her fun. The second you see the improper behavior, go out and clip a leash on her and lead her inside for a "time out" all alone. Don't say anything to her as you do this. Take her to a boxer-proof (is there any such thing?) bathroom or small bedroom where there's nothing fun for her to do and shut her inside (make sure there's plenty of light and ventilation--windows are a must). If she's going to be rowdy, she can do it by herself. After about 5 minutes, go back in, clip on the leash, take her back outside, and let her go. (If you're already practicing resource control, this will be much easier to do.) Then, if she does something cruddy, repeat the whole process. Let her know you're willing and able to show her what play behavior is okay and what is not. The key, as always, is consistency. If something's not okay now, it's not okay ever. And, more importantly when you get her out with stranger-dogs, what is okay now is always okay, unless different understood instructions are given.
