Being choked is neither bad or unusual for a valve.  If the ratio of (absolute) pressures :inlet/outlet is greater than 2, then the flow is choked.
Choked does not mean that the flow stops.
Choked does not mean that you can't get any additional flow through the selonoid valve.  Just open the valve more and you'll have more flow.  
It really only means that the actual capacity is less than that predicted by the noncritical Cv equation.  Once the deviation of the measured flow less than the predicted flow exceeds 2% the flow is said to have choked.  
Another thing that happens is if the flow is choked and tnothing else changes, it is possible to lower the downstream pressure additionally wouthout affecting the flowrate.  
Once the flow is choked: the math changes and you use a different equation.  Any manufacturer's sizing software is going to address this and automatically shift to the compressible flow routine. The compressible flow routine has 15 variables.  It is not fun.   If you are sizing valves by pencil, paper, and calculator you have too much free time. 

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