Not directly but there are a number of changes you could try.
If you are using the SCART lead then try unplugging both ends and reconnecting. It may have slightly oxidised over time and just the act of removing and reconnecting may improve the picture.
For a long time now most TVs sold have menu settings were you can change the brightness separately for each of the SCART/HDMI connections. Possibly the 9300T is connected to one of the TV's SCART/HDMI inputs where the brilliance has somehow been turned down. Using the TV's remote check the TV's menus to see if you can boost the brilliance for the 9300T connection.
If you are using the SCART lead that came with it then change the SCART lead. The very cheap (and some overpriced SCARTs) are very low quality and reduce the brilliance compared to one with better quality wires.
If you are using a SCART and your TV has an HDMI input then switch to an HDMI cable. Cheap ones are OK unless they are actually faulty. There will not be any loss of brightness via HDMI.