I disagree with support and agree with you. Keep it on the charger.

In an earlier era, with NiCd batteries, keeping a unit constantly on the charger was almost always a bad idea. (Some of the later designs corrected this) If the support person you spoke with learned about batteries from an old-timer, outdated advice was given. Lithium batteries love to be charged, hate to be fully discharged.

This is the advice that Sonos gave when them the Roam was originally released.  I’m quite sure because I intended to use the Roam permanently plugged in, and had no issues with it.  Though I haven’t really attempted to use the battery since setup.

Thanks @buzz, @melvimbe,

may they be referring to an issue of excessive heating ?

I understand the concern with heating. ROAM does warm when on the charger and, at least in the Northern Hemisphere, we are experiencing an unusually warm summer. Batteries don’t like heat. On the other hand, batteries degrade for each charge/discharge cycle. The rule of thumb is that batteries are good for approximately 800-1000 full cycles.

From a battery management perspective, if you want to avoid the heating, you’ll need to remove the charger at 100%, then allow the unit to discharge for a few days before charging again. You’d need to map out the best plan to keep the battery cool without accumulating too many charge/discharge cycles. Deep discharges are more stressful than shallow discharges. For me, this management routine would become an unwelcome chore.