That sounds like a problem with untuned queries, more than a problem with Reporting Services itself.
Have you looked into what the drop-downs are getting their data from? Is it a pre-defined list, or a query? If it's a query, have you gone through the standard steps for optimizing it? Like execution plans, index use, pre-caching, and so on?
- Gus "GSquared", RSVP, OODA, MAP, NMVP, FAQ, SAT, SQL, DNA, RNA, UOI, IOU, AM, PM, AD, BC, BCE, USA, UN, CF, ROFL, LOL, ETC
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