Hi Jenny
If I remember correctly you've got the spirit combi! which is the up grade to my origianal spirit..
Check that you've got the lunar lock tight, user the duffer of the magifying glass to check it's tight..
There's a couple of tricks to filling up the cartidge that helps to prevent air bubbles..
1, Take your insulin vial out the fridge to come up to room tempreture, before fillining
2, Ensure that you lubicate the inside of the cartridge, by moving the pungler back and forth several times
3, When you inject air into the vial, ensure vial is on table/hard surface and you aren't injecting air through the insulin..
4, Let the air push the plunger and fill the cartridge, this help to air at the top once full, a couple of gentle taps (I use a teaspoon) the remove seeable air.
5, once full take the needle fuller off and detach plunger, tap bottom of cartridge on table a couple of times..
6, Leave the filled cartrridge to stand for a while (30+ minutes if possible)
7, Before putting into pump, another couple of sharp taps on table, and check for air, reattach plunger if you need to remove any..
Another thing I've found that help air bubbles getting in the tubing is I always where my pump with the lunar lock facing downwards, then any air bubbles stays at the end of the cartridge out of the way of the tubing..
I was told by my training rep don't worry about champange bubbles won't make a difference so he said, I'm very sensitive to insulin for me they do make a difference..
I would phone Rouche up and ask if the could send you a sample of shorter tubes to try if you find the current one problematic then you can see what suits you best
Hope this helps