My freelander starts first time but after a couple of miles the ing light flickers the the srs light comes on then all the instruments go off for a few seconds after which time the car then carrys on as normal for the rest of the jorney i only use me freelander about once a fortnight any idears

i have a Freelander all the tweeters work, but only my driver side woofer plus the one in my boot under the floor where the tools are kept. Has anyone got any idears