Some of Baird's early inventions were not fully successful. In his twenties he tried to create diamonds by heating graphite and shorted out Glasgow's electricity supply. Later Baird invented a glass razor, which was rust-resistant, but shattered. Inspired by pneumatic tyres he attempted to make pneumatic shoes, but his prototype contained semi-inflated balloons, which burst. He also invented a thermal undersock (the Baird undersock), which was moderately successful. Baird suffered from cold feet, and after a number of trials, he found that an extra layer of cotton inside the sock provided warmth.  Baird's numerous other developments demonstrated his particular talent at invention. He was a visionary and began to dabble with electricity. In 1928, he developed an early video recording device, which he dubbed Phonovision. The system consisted of a large Nipkow disk attached by a mechanical linkage to a conventional 78-rpm record-cutting lathe. The result was a disc that could record and play back a 30-line video signal. Technical difficulties with the system prevented its further development, but some of the original phonodiscs have been preserved, and have since been restored by Donald McLean, a Scottish electrical engineer.  Baird's other developments were in fibre-optics, radio direction finding, infrared night viewing and radar. There is discussion about his exact contribution to the development of radar, for his wartime defence projects have never been officially acknowledged by the UK government. According to Malcolm Baird, his son, what is known is that in 1926 Baird filed a patent for a device that formed images from reflected radio waves, a device remarkably similar to radar, and that he was in correspondence with the British government at the time. The radar contribution is in dispute. According to some experts, Baird's "noctovision" is not radar. Unlike radar (except Doppler radar), Noctovision is incapable of determining the distance to the scanned subject. Noctovision also cannot determine the coordinates of the subject in three-dimensional space.

Answer this question "Were there any problems with it?" by extracting the answer from the text above.
Technical difficulties with the system prevented its further development, but some of the original phonodiscs have been preserved, and have since been restored by Donald McLean,