I find it more worrying that you believe you have to keep rebooting the phones every night to keep them stable.
5.4.1 has only been released last week and it would be of interest what issues you are suffering that make you reboot the phones daily.
Could you work with your Polycom reseller or provide me with the MAC address of a phone in question so I can point you to the relevant people?
Please ensure to provide some feedback if this reply has helped you so other users can profit from your experience.
Polycom Global Services
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