Pixelation across all channels last few weeks.

Hello, for the last few weeks I have been experiencing pixelation across multiple channels. We called support once and they were not effective at troubleshooting or fixing the issue. There have been no changes to our internal coax cables and this spans multiple boxes, so this may be related to the line outside. We have Triple Play and haven't noticed any internet of phone problems. Any assistance would be appreciated. Thank you!