Transducer options on DSM300 changed

[naz14]

Hi,
I have a Raymarine E120 MFD with a DSM300 and the speed/temp sensor on my Airmar B744V transducer recently failed, so I purchased a new Airmar speed/temp insert for the transducer, which I spliced into my transducer cable via an Airmar waterproof splice box. After finishing the installation I checked the operation of the transducer and found the temperature and depth working fine but NO speed indications. I then reset the DSM300 and went to configure the DSM300 for the B744V transducer and found the drop down list of transducers no longer listed the B744V transducer or any other 600 watt transducers. All of the transducers on the list were of the 1Kw variety. I know that prior to changing the speed/temp insert, my DSM300 was configured for a B744V transducer and it definitely showed up on the dropdown list. How can I configure the DSM for the correct transducer if it does not show up on the configuration drop down list and why did the list change? Thanks in advance for your help.