Welcome to the forums!
You may already know, but if you're using all the same drivers, there should not be any difference with bluetooth operation between Win7 Ultimate (64-bit?) and your original Win7 Home Premium 64-bit ASUS factory image.
It sounds like the notebook did find the speaker 2 or 3 times though?? I kind of expect it to work all the time or not at all (becauase of some software set up problem) if you didn't have any problems before.
1. If you stuck to all the original notebook drivers with your ASUS factory Win7 image when everything was working okay, make sure you get all the same drivers from the
ASUS G75VW download site here and not from Microsoft or other sources which may have unapproved versions.
Make sure your device manager is clean and you installed the Intel Chipset driver from the ASUS G75VW download site.
2. Can you think of any changes or updates you made to the 'working' Win7 image that weren't used for your new Win7 Ultimate install?
a. Check for any updates for your HDMX Jam Speakers. Don't think there should be a lot of settings to worry about, but try to remember if you did anything different to set them up last time?
b. Install the critical/important Windows updates (ignore the optional updates) to see if this makes any difference?
3. Have you tried your HDMX Jam Speakers with a different system (in the same area in case you are getting some interference if that's even possible with bluetooth?) to confirm everything is still okay with them?
4. Do you have a different bluetooth device to check with the notebook just to confirm the problem is on the notebook side?
Sorry, not really sure what the problem is, but hope this helps.
Also, another ROG member was looking for some portable speakers, and I mentioned your thread.
If you're interested, you may want to give them some feedback about your speakers when they were working at this
thread External speakers.
Thanks!