Usually, channel interference is caused if a device is outputting its picture on a RF frequency near an existing TV broadcast, however the LiteOn DVD recorders do not output its picture over RF from what I recall.
The first thing I would recommend trying would be to try moving the antenna (rabbit ears) about. If the interference decreases the further you move your antenna from the DVD recorder, then the antenna is picking up the inteference directly from the recorder, which in this case you’ll need to find another place to set up the antenna. Otherwise if the interference remains roughly the same regardless of where you move the antenna (or varies only a slight amount), then while the aerial may be picking up a clear signal, the interference is likely being added as the signal passes through the DVD recorder. In this case I would suggest using an RF amplifier as this should amplify the signal strength enough to overpower the inteference produced by the LiteOn.