What we are finding is that this may be an issue with using the Horizon Client in nested mode. Nested mode is needed for our IT users where they have a separate "productivity" and "admin" user account and linked clone.
We had a user launch the Horizon Client twice from their personal machine and login directly to each VM. Initially reports are that they are no longer seeing the issue. Since we use Blast and don't have GPU I suspect nested mode is overwhelming the first linked clone running the Horizon Client.
