pics are pretty blurry. how old is your cassette? could be that the teeth on your cog are worn and need to be replaced.
but as tiswas said, i'd adjust the L&H screws before replacing cassette.
@Hovis_Brown started
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pics are pretty blurry. how old is your cassette? could be that the teeth on your cog are worn and need to be replaced.
but as tiswas said, i'd adjust the L&H screws before replacing cassette.