Increase priority for channel changing?

[Jackal24]

I am using a USB-UIRT to change the channels on my cable boxes (no serial input). The problem is that I am using an older laptop to run sage. Every once in a while, the computer will become slightly bogged down. This is only really a problem when it tries to change channels. Sometimes it will be a little too slow sending the digits, and the cable box sees this delay as being too long and does not respond correctly.

For example, if I want to change to channel 113, the computer sends a signal for 1, then 1, then 3. Sometimes the cable box will pick this up as a command to change to channel 1, then channel 1 again, then channel 3. If I change the settings on the box so that an enter command is required, it sees it as channel 1 , nevermind took too long, channel 1, nevermind took too long, etc.

Is there any way to increase the priority of channel changing? Or maybe using girder?