I bought a SanDisk 256 GB flash drive to use with my iView 3500-STBII. The iView has PVR so I record OTA broadcasts frequently, and I needed more space than the 128 GB SanDisk flash drive I had been using. The recordings on the new 256 GB drive are choppy, with lots of tiling [not sure if that's the correct term]. I notice the 256 GB drive has a frame rate of 30 Hz and scans at 1920 x 1080, while the 128 GB is 60 Hz, 1920 x 1080. Can anyone tell me what I should do--exchange the 256 GB drive for one [or two] 128 GB drive? I don't know much about this stuff. Thanks!