We deliver DSL to customers, and everything worked fine until two days ago, when cistomers started to complain about not reaching a number of sites on the internet. The dsl in terminated at 3-layer at another Isp. We can not find any common sign in ip ranges, sites thats not working or termination geografic of customer. When the other isp configured ip tcp adjust mss on the ERX it worked again. Both isp claim to have done no changes that should have impact on this. Anyone experienced something alike?