I had the galaxy buds 1st gen using them with my galaxy active watch.
When playing music offline via spotify and going for a run/walk with the watch on my left arm, music would at times cut out, stutter, and generally suffer with the bluetooth connection. I could put the watch down on my bed, go into another room and all was fine, but as soon as the watch was on me, I had this occasional issue.
I bought the buds+ and the issue still persisted.
By default, the right earbud is the primary bluetooth bud with the left being the slave, meaning 100% of the signal is in the right bud.
If you intend to use with a watch on your left arm, or a device such as a phone that you keep in your left pocket, simply take out the left bud and pop in your ear and leave the right one in the case. When connected and music playing, pop out the right bud and place in your ear. The left earbud is then the primary bluetooth device and the right is the slave.
I've just had zero issues when going for my run and streaming music from my watch.
Whatever it is, it's fixed! Whether my watch suffers from low bluetooth signal I don't know. But I have read others on here have had issues when they put their phone in the back of their pocket. This never happened with me and always had perfect connections. It was just with my watch. This way, my watch and left earbud are constantly close together so I have no issues at all.