NR State laws for muni bond interest

[Kea]

Living in TX I don't do a lot of state returns.

Client has a (federal) tax-exempt municipal bond mutual fund.  The fund has income from almost all 50 states.  Are there any states that will require an tax return to report non-resident muni interest?

When filing a resident tax return, a state will usually treat the income as taxable if the muni interest is from another state.  But will other states require you to file a NR return?

Thanks