- Check the carrier/network configuration and settings are correct - search wiki.maemo.org for fmms.
- Try using Havoc mode to force the connection.
- Sometimes fmms doesn't work when connected to 3G for browsing b/c it needs a WAP connection, which IIRC uses the same radio receiver. So, stop browsing or use wifi where possible.
- Ensure you have a reasonable connection.to GSM/3G.