Hi donaldfromglasgow,
and welcome to this Apple (user-to-user) Community.
Re: "Music on Tahoe using 100% resources - driving me mad!"
Re-indexing etc., often goes on in the background for quite some time after a major upgrade, using memory / power etc. until the process completes.
Wondering ...
Is MacOS 26 installed, or MacOS 26.0.1 ?
(MacOS 26.0.1) included bug-fixes and security updates)
If 26.0.1 is installed, and enough time has elapsed to allow for the upgrade/ update process to complete: Have you tried restarting your Mac (Apple menu > Restart) ?
Restarting deletes temporary files, re-establishes connections, may update recent setting changes etc,. and often restores order when something is not working as expected.
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Re: "it now seems very sluggish, especially on Music"
Quite apart from external storage space, iCloud, etc:
Does your Mac itself have enough memory / storage space free ?
(A mac generally needs at least 50 Gb free in which to do all we ask it to do.)
(You can check in Apple menu > System Settings > General > Storage)
NB: Reminder: Always wise to back up Mac first, if you need to delete anything to make space
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Re: " ... and every time I now play something, the spinning ball appears."
If you use third-party (non-Apple) apps on your Mac:
There may be interference issues with your Apple apps.
✽ Unnecessary apps like ad-blockers, virus checkers, cleaners and the like (even VPN) often cause issues. If installed, you can try turning them off (or use uninstallers from their developers) to see if that helps.
✽ Out-of-date browser extensions can also cause issues ... turn off / uninstall / or update if possible.
✽ Ensure no excessive amounts of blocked contacts have accrued from a third-party app.
✽ Any third-party apps you find necessary may need updating in order to remain compatible, and not cause issues:
Apple Support also have an article online that may be helpful:
See: What o do: If your Mac runs slowly - Apple Support
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Re: "Has anyone else experienced this with Tahoe or is it just me,
and if so, is there a workround which makes Music better?"
Unless others with similar issues reply to your post, we have no way of knowing for sure.
We are all Apple users, like yourself in the community. We don't get to see the feedback sent to Apple, or the issues / cases that Apple Support gets asked about. Many issues do turn up in the community, after major upgrades. Many posts are replied to one by one by various community members who volunteer their time and efforts.
It is up to us individually whether we choose to upgrade ASAP to explore and use the new features right away, or whether we wait and see whether there are the (almost inevitable) software bugs and bug-fixes once all the different hardware models begin to use the upgrade, then upgrade once things settle down. (Many of us do the first, many, the second.)
All the best :-)
