SOAP exception when dealing with XMLA

We got a web application which accessing SQL Analysis Service through XMLA. Some times when we accessing it gives a SOAP exception. We tried everything (restating services and server also) but failed. Reinstalling XMLA SDK solved this problem but as you can understand it’s not the solution since this thing happening several times per day.

Today I changed application pool of XMLA web service and guess what? It solved the problem. So I create a dedicated application pool for XMLA and things going smoothly now. But not sure what will happen next. If this will work well, I'll add our web application also to that application pool.