Notes get stuck in SampleTank using Alesis ioDock and Sonar

[cgplazav]

I'm using Sonar 6.2 under iOS 6.1.2. I have the latest avaiable version of SampleTank. I'm using SampleTank in conjunction with a JV1080, controlled by Sonar. I'm using 2 instruments in Sampletank (cello and flute). Just after launching the application everything works fine but after a few minutes, notes start to get stuck and I continuously need to hit the panic button. The problem gets worse with time so I would assume the problem must be related to some buffer. I changed the latency to ULTRA LOW, but the problem remained so I put latency back to LOW. Is there anything else I can adjust in order to avoid this problem?

Thanks

Carlos