Check that you are using the correct needle for your machine--a needle of the incorrect length will most likely hit where it shouldn't. Then be sure to use a heavy enough needle so it will not bend when stitching heavy fabric. Next, do not pull or push the fabric when stitching as that will tend to bend the needle. If those check out, then there is most likely a timing issue where the needle is arriving at the wrong time. Best to take it for service.
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Check that you are using the correct needle for your machine--a needle of the incorrect length will most likely hit where it shouldn't. Then be sure to use a heavy enough needle so it will not bend when stitching heavy fabric. Next, do not pull or push the fabric when stitching as that will tend to bend the needle. If those check out, then there is most likely a timing issue where the needle is arriving at the wrong time. Best to take it for service.
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