Solar Charge Controller firmware v1.64 contains a few model specific changes:

• SmartSolar 75/10 and 75/15: fix stability issue that could cause it to freeze during shutdown and startup, only continuing after a power cycle. Applies only to HQ2235 and later.
• SmartSolar 100/20: fix stability issue that could cause it to lock up when starting up under high solar potential.
• SmartSolar 100/30-12V: internal improvements

How to install:

This firmware update is available now as a manual update in Dropbox, the Victron Professsional firmware section, and via VRM firmware update.

It will be included in the next release of VictronConnect. Until that release the device will show as up-to-date in VictronConnect unless the file is manually updated. 

Please see the firmware update section of the SmartSolar manual for firmware update details, and VictronConnect Firmware updates section for manual updating.