Good evening,
I don't think they are bandsmen, no trade badges on their arms. The right hand one of the 2 is wearing sabre slings as well which bandsmen didn't. They all have spurs except the man on the left in trousers. I also think they should all be wearing the braids on the left arm, quite common on yeomanry units I believe.
All mounted troops wore standard infantry boots with either leather gaiters or puttees depending on type of unit. These men are not wearing any as you can see socks between boots and jodphurs. As mounted men they would be worn wound from the top down as opposed to bottom up for infantry.
John915