Generally I would say it is a entry angle issue, however because you said this is a recent problem I figure it might be worth suggesting that it might be the center, be that you are bowling at the same center. When a local center here replaced their pins and did some work on the machines a few machines off-set the 7 pin, making leaving it with a 10 a lot easier, the problem was fixed and now carry is back to "normal"... but hey, who knows right, although it is most likely a entry angle issue.