This sounds like it's not the original neck, and not a neck with an octave key that fits properly. Is that the case? If so, and if the 'fix' your tech tried doesn't work, then sure, that's a good reason to find the proper neck for that horn, or at least one where the octave key works.I thought I mentioned already but... He says that when I use the octave key it was not always moving the mechanism to open/close the pad on the neck. He modified the part on the sax that moves the neck mechanism by extending the pin up so it met up with ring on the neck better. He believes that this is why I am having issues.
So basically from D2 to G2 something is still funny and you have to adjust your blowing to get those notes out ?Another thing that might help is that the problem (playing in a higher octave) occurs when I go from the lower register to D2 and also starting with D2. I have spent a lot of time on my breathing and can overcome this when I am very focused.