The firmware for the AP-6xx is on the AP already, and you can use the in-product update to get to the latest recommended version. That is probably why there is no factory image available (yet).
For the slow performance, that can also be a client/driver issues, or an issue that the encryption for CNSA 192bit is not supported in the hardware of your clients and performed in sotfware with a lower performance. This definetely needs to be further investigated, so I would +1 the recommendation to get TAC involved.
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Herman Robers
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If you have urgent issues, always contact your Aruba partner, distributor, or Aruba TAC Support. Check
https://www.arubanetworks.com/support-services/contact-support/ for how to contact Aruba TAC. Any opinions expressed here are solely my own and not necessarily that of Hewlett Packard Enterprise or Aruba Networks.
In case your problem is solved, please invest the time to post a follow-up with the information on how you solved it. Others can benefit from that.
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