There are several positions of the tongue that will allow the overblow to sound in hole one, but most of them are not stable.
In my opinion the best way to play this is to put your toungue on the bottom of your mouth and try to get the tongue as low as possible for the entire length of the tongue.
The feeling is a little like having a hot potato in your mouth that you are trying to cool down by blowing past it.
Choke the blowreed with the tongue in that position. If you are able to get a relaxed but solid choke on the blowreed, you should be able to play a stable overblow.
Anyway i'm going to wax the rivets to see if that cures it. Either that or my embouchure is slightly wrong and that's what allows the noise, unrelated to the proper notes that should be played, to come in.
I also notice that after spending a long time practicing the blow bends on hole 10 that when i play the draw reed it's choked off and won't sound. I think you mentioned condensation before when i spoke to you about the #1 overblow. Is it the same thing here?
Thanks
Gary
Thanks again, your replies really help me out a lot.
I need one hole harmonica for alarm pneumatic
thanks