If two IP channels are consistently giving the IPC6023 error on tune, whilst other channels are consistently working, this definitely suggests an issue within the network rather than your individual home setup.
I'm looking into this for you.
I've sent you a PM.
We would like you to assist us with some troubleshooting to try and find the cause of this issue.
Just to summarise;
We fixed this fault by performing a software reset on the Youview STB.
This was an unusal case in that live viewing of two specific IP channels resulted in an IPC6023 error follwing tuning to the channel.
However, recordings for these same two IP channels completed and played back successfully.
We are currently trying to understand what could cause an STB to get into a state where recordings work, but live viewing results in an IPC6023 error, for a subset of IP channels.
I would be interested to hear from anyone who has experienced this type of issue.
I am seeing exactly the same issue. I have not gone through the full reset of the box yet, but all of the Sky cinema channels stream well apart form 502.