We have a problem about GC/MS(VARIAN). Five days ago, we cleaned the ion volume of the MS part. But after that, we have no signal. Then we follow the advice of VARIAN's technic service and replace the detector and the electronic card of the detector. But the problem remains. Every time we start the software the system warns that the baseline is too low! We examine all the parts of the GC-MS. there is no leaks. All the parts are connected well. We failed to solve it. Have you anyone the same problem? or an idea? thanks a lot.